diff --git a/.gn b/.gn
new file mode 100644
index 00000000000..fc54abe46e9
--- /dev/null
+++ b/.gn
@@ -0,0 +1,14 @@
+# Copyright 2016 The Dart project authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This file is used by the gn meta-buildsystem find the root of the source tree
+# and to set startup options.
+
+# The location of the build configuration file.
+buildconfig = "//build/config/BUILDCONFIG.gn"
+
+# The secondary source root is a parallel directory tree where
+# GN build files are placed when they can not be placed directly
+# in the source tree, e.g. for third party source trees.
+secondary_source = "//build/secondary/"
diff --git a/BUILD.gn b/BUILD.gn
new file mode 100644
index 00000000000..d86d84a0d05
--- /dev/null
+++ b/BUILD.gn
@@ -0,0 +1,21 @@
+# Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+# This target will be built if no target is specified when invoking ninja.
+group("default") {
+  deps = [
+    ":runtime",
+  ]
+}
+
+group("runtime") {
+  deps = [
+    "//runtime/bin:dart",
+    "//runtime/bin:dart_bootstrap($host_toolchain)",
+    "//runtime/bin:run_vm_tests",
+    "//runtime/bin:process_test",
+    "//runtime/bin:test_extension",
+    "//runtime/bin:sample_extension",
+  ]
+}
diff --git a/DEPS b/DEPS
index 81704db1680..1c952b5cc92 100644
--- a/DEPS
+++ b/DEPS
@@ -30,8 +30,7 @@ vars = {
   "gyp_rev": "@6ee91ad8659871916f9aa840d42e1513befdf638",
   "co19_rev": "@d4767b4caea3c5828ad8e053cd051d44a59061af",
 
-  # Revisions of GN/Mojo/Flutter related dependencies.
-  "base_revision": "@672b04e54b937ec899429a6bd5409c5a6300d151",
+  # Revisions of GN related dependencies.
   "buildtools_revision": "@565d04e8741429fb1b4f26d102f2c6c3b849edeb",
 
   "gperftools_revision": "@7822b5b0b9fa7e016e1f6b46ea86f26f4691a457",
@@ -45,7 +44,7 @@ vars = {
   "barback_tag" : "@0.15.2+9",
   "bazel_worker_tag": "@0.1.1",
   "boolean_selector_tag" : "@1.0.2",
-  "boringssl_gen_rev": "@ef64e76254a12ee08a7142c825aa59ea32005958",
+  "boringssl_gen_rev": "@1e8e5da213d0d5b1d50fcc1356c4783091bcc20d",
   "boringssl_rev" : "@8d343b44bbab829d1a28fdef650ca95f7db4412e",
   "charcode_tag": "@1.1.0",
   "chrome_rev" : "@19997",
@@ -131,11 +130,7 @@ deps = {
   Var("dart_root") + "/third_party/gyp":
       Var('chromium_git') + '/external/gyp.git' + Var("gyp_rev"),
 
-  # Stuff needed for GN/Mojo/Flutter.
-  Var("dart_root") + "/base":
-     Var('chromium_git') + '/external/github.com/domokit/base'
-     + Var('base_revision'),
-
+  # Stuff needed for GN build.
   Var("dart_root") + "/buildtools":
      Var('chromium_git') + '/chromium/buildtools.git' +
      Var('buildtools_revision'),
@@ -363,6 +358,83 @@ deps_os = {
 # TODO(iposva): Move the necessary tools so that hooks can be run
 # without the runtime being available.
 hooks = [
+  # Pull GN binaries. This needs to be before running GYP below.
+  {
+    'name': 'gn_linux64',
+    'pattern': '.',
+    'action': [
+      'download_from_google_storage',
+      '--no_auth',
+      '--no_resume',
+      '--quiet',
+      '--platform=linux*',
+      '--bucket',
+      'chromium-gn',
+      '-s',
+      Var('dart_root') + '/buildtools/linux64/gn.sha1',
+    ],
+  },
+  {
+    'name': 'gn_mac',
+    'pattern': '.',
+    'action': [
+      'download_from_google_storage',
+      '--no_auth',
+      '--no_resume',
+      '--quiet',
+      '--platform=darwin',
+      '--bucket',
+      'chromium-gn',
+      '-s',
+      Var('dart_root') + '/buildtools/mac/gn.sha1',
+    ],
+  },
+  {
+    'name': 'gn_win',
+    'pattern': '.',
+    'action': [
+      'download_from_google_storage',
+      '--no_auth',
+      '--no_resume',
+      '--quiet',
+      '--platform=win*',
+      '--bucket',
+      'chromium-gn',
+      '-s',
+      Var('dart_root') + '/buildtools/win/gn.exe.sha1',
+    ],
+  },
+  # Pull clang-format binaries using checked-in hashes.
+  {
+    'name': 'clang_format_linux',
+    'pattern': '.',
+    'action': [
+      'download_from_google_storage',
+      '--no_auth',
+      '--no_resume',
+      '--quiet',
+      '--platform=linux*',
+      '--bucket',
+      'chromium-clang-format',
+      '-s',
+      Var('dart_root') + '/buildtools/linux64/clang-format.sha1',
+    ],
+  },
+  {
+    'name': 'clang_format_mac',
+    'pattern': '.',
+    'action': [
+      'download_from_google_storage',
+      '--no_auth',
+      '--no_resume',
+      '--quiet',
+      '--platform=darwin',
+      '--bucket',
+      'chromium-clang-format',
+      '-s',
+      Var('dart_root') + '/buildtools/mac/clang-format.sha1',
+    ],
+  },
   {
     'name': 'd8_testing_binaries',
     'pattern': '.',
@@ -497,6 +569,12 @@ hooks = [
       Var('dart_root') + "/third_party/clang.tar.gz.sha1",
     ],
   },
+  {
+    # Pull clang if needed or requested via GYP_DEFINES.
+    'name': 'gn_clang',
+    'pattern': '.',
+    'action': ['python', 'sdk/tools/clang/scripts/update.py', '--if-needed'],
+  },
   {
     "pattern": ".",
     "action": ["python", Var("dart_root") + "/tools/gyp_dart.py"],
diff --git a/build/config/BUILD.gn b/build/config/BUILD.gn
index 0af90cd06d4..93243a1fc70 100644
--- a/build/config/BUILD.gn
+++ b/build/config/BUILD.gn
@@ -2,433 +2,23 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/allocator.gni")
-import("//build/config/chrome_build.gni")
-import("//build/config/crypto.gni")
-import("//build/config/features.gni")
-import("//build/config/ui.gni")
-import("//build/module_args/v8.gni")
-
-declare_args() {
-  # When set, turns off the (normally-on) iterator debugging and related stuff
-  # that is normally turned on for Debug builds. These are generally useful for
-  # catching bugs but in some cases may cause conflicts or excessive slowness.
-  disable_iterator_debugging = false
-
-  # Set to true to not store any build metadata, e.g. ifdef out all __DATE__
-  # and __TIME__. Set to 0 to reenable the use of these macros in the code
-  # base. See http://crbug.com/314403.
-  #
-  # Continue to embed build meta data in Official builds, basically the
-  # time it was built.
-  # TODO(maruel): This decision should be revisited because having an
-  # official deterministic build has high value too but MSVC toolset can't
-  # generate anything deterministic with WPO enabled AFAIK.
-  dont_embed_build_metadata = !is_official_build
-
-  # Set to true to enable dcheck in Release builds.
-  dcheck_always_on = false
-
-  # Set to true to compile with the OpenGL ES 2.0 conformance tests.
-  internal_gles2_conform_tests = false
-}
-
-# TODO(brettw) Most of these should be removed. Instead of global feature
-# flags, we should have more modular flags that apply only to a target and its
-# dependents. For example, depending on the "x11" meta-target should define
-# USE_X11 for all dependents so that everything that could use X11 gets the
-# define, but anything that doesn't depend on X11 doesn't see it.
-#
-# For now we define these globally to match the current GYP build.
-config("feature_flags") {
-  # TODO(brettw) this probably needs to be parameterized.
-  defines = [ "V8_DEPRECATION_WARNINGS" ]  # Don't use deprecated V8 APIs anywhere.
-
-  if (cld_version > 0) {
-    defines += [ "CLD_VERSION=$cld_version" ]
-  }
-  if (enable_mdns) {
-    defines += [ "ENABLE_MDNS=1" ]
-  }
-  if (enable_notifications) {
-    defines += [ "ENABLE_NOTIFICATIONS" ]
-  }
-  if (enable_pepper_cdms) {
-    # TODO(brettw) should probably be "=1"
-    defines += [ "ENABLE_PEPPER_CDMS" ]
-  }
-  if (enable_browser_cdms) {
-    # TODO(brettw) should probably be "=1"
-    defines += [ "ENABLE_BROWSER_CDMS" ]
-  }
-  if (enable_plugins) {
-    defines += [ "ENABLE_PLUGINS=1" ]
-  }
-  if (enable_basic_printing || enable_print_preview) {
-    # Convenience define for ENABLE_BASIC_PRINTING || ENABLE_PRINT_PREVIEW.
-    defines += [ "ENABLE_PRINTING=1" ]
-    if (enable_basic_printing) {
-      # Enable basic printing support and UI.
-      defines += [ "ENABLE_BASIC_PRINTING=1" ]
-    }
-    if (enable_print_preview) {
-      # Enable printing with print preview.
-      # Can be defined without ENABLE_BASIC_PRINTING.
-      defines += [ "ENABLE_PRINT_PREVIEW=1" ]
-    }
-  }
-  if (enable_spellcheck) {
-    defines += [ "ENABLE_SPELLCHECK=1" ]
-  }
-  if (use_platform_spellchecker) {
-    defines += [ "USE_PLATFORM_SPELLCHECKER=1" ]
-  }
-  if (dont_embed_build_metadata) {
-    defines += [ "DONT_EMBED_BUILD_METADATA" ]
-  }
-  if (dcheck_always_on) {
-    defines += [ "DCHECK_ALWAYS_ON=1" ]
-  }
-  if (use_udev) {
-    # TODO(brettw) should probably be "=1".
-    defines += [ "USE_UDEV" ]
-  }
-  if (ui_compositor_image_transport) {
-    # TODO(brettw) should probably be "=1".
-    defines += [ "UI_COMPOSITOR_IMAGE_TRANSPORT" ]
-  }
-  if (use_ash) {
-    defines += [ "USE_ASH=1" ]
-  }
-  if (use_aura) {
-    defines += [ "USE_AURA=1" ]
-  }
-  if (use_glfw) {
-    defines += [ "USE_GLFW=1" ]
-  }
-  if (use_pango) {
-    defines += [ "USE_PANGO=1" ]
-  }
-  if (use_cairo) {
-    defines += [ "USE_CAIRO=1" ]
-  }
-  if (use_clipboard_aurax11) {
-    defines += [ "USE_CLIPBOARD_AURAX11=1" ]
-  }
-  if (use_default_render_theme) {
-    defines += [ "USE_DEFAULT_RENDER_THEME=1" ]
-  }
-  if (use_openssl) {
-    defines += [ "USE_OPENSSL=1" ]
-  }
-  if (use_openssl_certs) {
-    defines += [ "USE_OPENSSL_CERTS=1" ]
-  }
-  if (use_nss_certs) {
-    defines += [ "USE_NSS_CERTS=1" ]
-  }
-  if (use_ozone) {
-    defines += [ "USE_OZONE=1" ]
-  }
-  if (use_x11) {
-    defines += [ "USE_X11=1" ]
-  }
-  if (use_allocator != "tcmalloc") {
-    defines += [ "NO_TCMALLOC" ]
-  }
-  if (is_asan || is_lsan || is_tsan || is_msan || is_ios) {
-    defines += [
-      "MEMORY_TOOL_REPLACES_ALLOCATOR",
-      "MEMORY_SANITIZER_INITIAL_SIZE",
-    ]
-  }
-  if (is_asan) {
-    defines += [ "ADDRESS_SANITIZER" ]
-  }
-  if (is_lsan) {
-    defines += [
-      "LEAK_SANITIZER",
-      "WTF_USE_LEAK_SANITIZER=1",
-    ]
-  }
-  if (is_tsan) {
-    defines += [
-      "THREAD_SANITIZER",
-      "DYNAMIC_ANNOTATIONS_EXTERNAL_IMPL=1",
-      "WTF_USE_DYNAMIC_ANNOTATIONS_NOIMPL=1",
-    ]
-  }
-  if (is_msan) {
-    defines += [ "MEMORY_SANITIZER" ]
-  }
-  if (enable_webrtc) {
-    defines += [ "ENABLE_WEBRTC=1" ]
-  }
-  if (disable_ftp_support) {
-    defines += [ "DISABLE_FTP_SUPPORT=1" ]
-  }
-  if (!enable_nacl) {
-    defines += [ "DISABLE_NACL" ]
-  }
-  if (enable_extensions) {
-    defines += [ "ENABLE_EXTENSIONS=1" ]
-  }
-  if (enable_configuration_policy) {
-    defines += [ "ENABLE_CONFIGURATION_POLICY" ]
-  }
-  if (enable_task_manager) {
-    defines += [ "ENABLE_TASK_MANAGER=1" ]
-  }
-  if (enable_themes) {
-    defines += [ "ENABLE_THEMES=1" ]
-  }
-  if (enable_captive_portal_detection) {
-    defines += [ "ENABLE_CAPTIVE_PORTAL_DETECTION=1" ]
-  }
-  if (enable_session_service) {
-    defines += [ "ENABLE_SESSION_SERVICE=1" ]
-  }
-  if (enable_rlz) {
-    defines += [ "ENABLE_RLZ" ]
-  }
-  if (enable_plugin_installation) {
-    defines += [ "ENABLE_PLUGIN_INSTALLATION=1" ]
-  }
-  if (enable_app_list) {
-    defines += [ "ENABLE_APP_LIST=1" ]
-  }
-  if (enable_settings_app) {
-    defines += [ "ENABLE_SETTINGS_APP=1" ]
-  }
-  if (enable_supervised_users) {
-    defines += [ "ENABLE_SUPERVISED_USERS=1" ]
-  }
-  if (enable_service_discovery) {
-    defines += [ "ENABLE_SERVICE_DISCOVERY=1" ]
-  }
-  if (enable_autofill_dialog) {
-    defines += [ "ENABLE_AUTOFILL_DIALOG=1" ]
-  }
-  if (enable_wifi_bootstrapping) {
-    defines += [ "ENABLE_WIFI_BOOTSTRAPPING=1" ]
-  }
-  if (enable_image_loader_extension) {
-    defines += [ "IMAGE_LOADER_EXTENSION=1" ]
-  }
-  if (enable_remoting) {
-    defines += [ "ENABLE_REMOTING=1" ]
-  }
-  if (enable_google_now) {
-    defines += [ "ENABLE_GOOGLE_NOW=1" ]
-  }
-  if (enable_one_click_signin) {
-    defines += [ "ENABLE_ONE_CLICK_SIGNIN" ]
-  }
-  if (enable_hidpi) {
-    defines += [ "ENABLE_HIDPI=1" ]
-  }
-  if (enable_topchrome_md) {
-    defines += [ "ENABLE_TOPCHROME_MD=1" ]
-  }
-  if (proprietary_codecs) {
-    defines += [ "USE_PROPRIETARY_CODECS" ]
-  }
-  if (enable_hangout_services_extension) {
-    defines += [ "ENABLE_HANGOUT_SERVICES_EXTENSION=1" ]
-  }
-  if (v8_use_external_startup_data) {
-    defines += [ "V8_USE_EXTERNAL_STARTUP_DATA" ]
-  }
-  if (enable_background) {
-    defines += [ "ENABLE_BACKGROUND=1" ]
-  }
-  if (enable_pre_sync_backup) {
-    defines += [ "ENABLE_PRE_SYNC_BACKUP" ]
-  }
-  if (enable_video_hole) {
-    defines += [ "VIDEO_HOLE=1" ]
-  }
-  if (safe_browsing_mode == 1) {
-    defines += [ "FULL_SAFE_BROWSING" ]
-    defines += [ "SAFE_BROWSING_CSD" ]
-    defines += [ "SAFE_BROWSING_DB_LOCAL" ]
-    defines += [ "SAFE_BROWSING_SERVICE" ]
-  } else if (safe_browsing_mode == 2) {
-    defines += [ "MOBILE_SAFE_BROWSING" ]
-    defines += [ "SAFE_BROWSING_SERVICE" ]
-  } else if (safe_browsing_mode == 3) {
-    defines += [ "MOBILE_SAFE_BROWSING" ]
-    defines += [ "SAFE_BROWSING_DB_REMOTE" ]
-    defines += [ "SAFE_BROWSING_SERVICE" ]
-  }
-  if (is_official_build) {
-    defines += [ "OFFICIAL_BUILD" ]
-  }
-  if (is_chrome_branded) {
-    defines += [ "GOOGLE_CHROME_BUILD" ]
-  } else {
-    defines += [ "CHROMIUM_BUILD" ]
-  }
-  if (enable_media_router) {
-    defines += [ "ENABLE_MEDIA_ROUTER=1" ]
-  }
-  if (enable_webvr) {
-    defines += [ "ENABLE_WEBVR" ]
-  }
-  if (is_fnl) {
-    defines += [ "HAVE_SYS_QUEUE_H_=0" ]
-  }
-}
-
 # Debug/release ----------------------------------------------------------------
 
 config("debug") {
   defines = [
-    "_DEBUG",
-    "DYNAMIC_ANNOTATIONS_ENABLED=1",
-    "WTF_USE_DYNAMIC_ANNOTATIONS=1",
+    "DEBUG",
   ]
-
-  if (is_nacl) {
-    defines += [ "DYNAMIC_ANNOTATIONS_PREFIX=NACL_" ]
-  }
-
-  if (is_win) {
-    if (disable_iterator_debugging) {
-      # Iterator debugging is enabled by the compiler on debug builds, and we
-      # have to tell it to turn it off.
-      defines += [ "_HAS_ITERATOR_DEBUGGING=0" ]
-    }
-  } else if (is_linux && !is_android && current_cpu == "x64" &&
-             !disable_iterator_debugging) {
-    # Enable libstdc++ debugging facilities to help catch problems early, see
-    # http://crbug.com/65151 .
-    # TODO(phajdan.jr): Should we enable this for all of POSIX?
-    defines += [ "_GLIBCXX_DEBUG=1" ]
-  }
 }
 
 config("release") {
-  defines = [ "NDEBUG" ]
-
-  # Sanitizers.
-  # TODO(GYP) The GYP build has "release_valgrind_build == 0" for this
-  # condition. When Valgrind is set up, we need to do the same here.
-  if (is_tsan) {
-    defines += [
-      "DYNAMIC_ANNOTATIONS_ENABLED=1",
-      "WTF_USE_DYNAMIC_ANNOTATIONS=1",
-    ]
-  } else {
-    defines += [ "NVALGRIND" ]
-    if (!is_nacl) {
-      # NaCl always enables dynamic annotations. Currently this value is set to
-      # 1 for all .nexes.
-      defines += [ "DYNAMIC_ANNOTATIONS_ENABLED=0" ]
-    }
-  }
+  defines = [
+    "NDEBUG"
+  ]
 }
 
-# Default libraries ------------------------------------------------------------
-
-# This config defines the default libraries applied to all targets.
-config("default_libs") {
-  if (is_win) {
-    # TODO(brettw) this list of defaults should probably be smaller, and
-    # instead the targets that use the less common ones (e.g. wininet or
-    # winspool) should include those explicitly.
-    libs = [
-      "advapi32.lib",
-      "comdlg32.lib",
-      "dbghelp.lib",
-      "delayimp.lib",
-      "dnsapi.lib",
-      "gdi32.lib",
-      "kernel32.lib",
-      "msimg32.lib",
-      "odbc32.lib",
-      "odbccp32.lib",
-      "ole32.lib",
-      "oleaut32.lib",
-      "psapi.lib",
-      "shell32.lib",
-      "shlwapi.lib",
-      "user32.lib",
-      "usp10.lib",
-      "uuid.lib",
-      "version.lib",
-      "wininet.lib",
-      "winmm.lib",
-      "winspool.lib",
-      "ws2_32.lib",
-
-      # Please don't add more stuff here. We should actually be making this
-      # list smaller, since all common things should be covered. If you need
-      # some extra libraries, please just add a libs = [ "foo.lib" ] to your
-      # target that needs it.
-    ]
-  } else if (is_android) {
-    # Android uses -nostdlib so we need to add even libc here.
-    libs = [
-      # TODO(brettw) write a version of this, hopefully we can express this
-      # without forking out to GCC just to get the library name. The android
-      # toolchain directory should probably be extracted into a .gni file that
-      # this file and the android toolchain .gn file can share.
-      #   # Manually link the libgcc.a that the cross compiler uses.
-      #   '<!(<(android_toolchain)/*-gcc -print-libgcc-file-name)',
-      "c",
-      "dl",
-      "m",
-    ]
-  } else if (is_mac) {
-    libs = [
-      "AppKit.framework",
-      "ApplicationServices.framework",
-      "Carbon.framework",
-      "CoreFoundation.framework",
-      "Foundation.framework",
-      "IOKit.framework",
-      "Security.framework",
-      "OpenGL.framework",
-    ]
-  } else if (is_ios) {
-    # The libraries listed here will be specified for both the target and the
-    # host. Only the common ones should be listed here.
-    libs = [
-      "CoreFoundation.framework",
-      "CoreGraphics.framework",
-      "CoreText.framework",
-      "Foundation.framework",
-    ]
-  } else if (is_linux) {
-    libs = [ "dl" ]
-  }
-}
-
-# Add this config to your target to enable precompiled headers.
-#
-# On Windows, precompiled headers are done on a per-target basis. If you have
-# just a couple of files, the time it takes to precompile (~2 seconds) can
-# actually be longer than the time saved. On a Z620, a 100 file target compiles
-# about 2 seconds faster with precompiled headers, with greater savings for
-# larger targets.
-#
-# Recommend precompiled headers for targets with more than 50 .cc files.
-config("precompiled_headers") {
-  # TODO(brettw) enable this when GN support in the binary has been rolled.
-  #if (is_win) {
-  if (false) {
-    # This is a string rather than a file GN knows about. It has to match
-    # exactly what's in the /FI flag below, and what might appear in the source
-    # code in quotes for an #include directive.
-    precompiled_header = "build/precompile.h"
-
-    # This is a file that GN will compile with the above header. It will be
-    # implicitly added to the sources (potentially multiple times, with one
-    # variant for each language used in the target).
-    precompiled_source = "//build/precompile.cc"
-
-    # Force include the header.
-    cflags = [ "/FI$precompiled_header" ]
-  }
+config("product") {
+  defines = [
+    "NDEBUG",
+    "PRODUCT",
+  ]
 }
diff --git a/build/config/BUILDCONFIG.gn b/build/config/BUILDCONFIG.gn
index e22b29aa690..09527af891a 100644
--- a/build/config/BUILDCONFIG.gn
+++ b/build/config/BUILDCONFIG.gn
@@ -38,17 +38,8 @@ if (target_os == "") {
   target_os = host_os
 }
 
-if (target_cpu == "") {
-  if (target_os == "android") {
-    # If we're building for Android, we should assume that we want to
-    # build for ARM by default, not the host_cpu (which is likely x64).
-    # This allows us to not have to specify both target_os and target_cpu
-    # on the command line.
-    target_cpu = "arm"
-  } else {
-    target_cpu = host_cpu
-  }
-}
+assert(host_cpu != "")
+assert(target_cpu != "")
 
 if (current_cpu == "") {
   current_cpu = target_cpu
@@ -110,28 +101,23 @@ if (current_os == "") {
 # - Don't call exec_script inside declare_args. This will execute the script
 #   even if the value is overridden, which is wasteful. See first bullet.
 
+# There is no component build for the Dart VM, but build files in some
+# dependencies check this.
+is_component_build = false
+
 declare_args() {
-  # How many symbols to include in the build. This affects the performance of
-  # the build since the symbols are large and dealing with them is slow.
-  #   2 means regular build with symbols.
-  #   1 means minimal symbols, usually enough for backtraces only.
-  #   0 means no symbols.
-  #   -1 means auto-set (off in release, regular in debug).
-  symbol_level = -1
-
-  # Component build.
-  is_component_build = false
-
   # Debug build.
   is_debug = true
 
-  # Whether we're a traditional desktop unix.
-  is_desktop_linux = current_os == "linux" && current_os != "chromeos"
+  # Release build.
+  is_release = false
+
+  # Product build.
+  is_product = false
 
   # Set to true when compiling with the Clang compiler. Typically this is used
   # to configure warnings.
-  is_clang = current_os == "mac" || current_os == "ios" ||
-             current_os == "linux" || current_os == "chromeos"
+  is_clang = current_os == "mac" || current_os == "linux"
 
   # Compile for Address Sanitizer to find memory bugs.
   is_asan = false
@@ -144,15 +130,6 @@ declare_args() {
 
   # Compile for Thread Sanitizer to find threading bugs.
   is_tsan = false
-
-  if (current_os == "chromeos") {
-    # Allows the target toolchain to be injected as arguments. This is needed
-    # to support the CrOS build system which supports per-build-configuration
-    # toolchains.
-    cros_use_custom_toolchain = false
-  }
-
-  # DON'T ADD MORE FLAGS HERE. Read the comment above.
 }
 
 # =============================================================================
@@ -176,7 +153,6 @@ declare_args() {
 if (current_os == "win") {
   is_android = false
   is_chromeos = false
-  is_fnl = false
   is_ios = false
   is_linux = false
   is_mac = false
@@ -186,7 +162,6 @@ if (current_os == "win") {
 } else if (current_os == "mac") {
   is_android = false
   is_chromeos = false
-  is_fnl = false
   is_ios = false
   is_linux = false
   is_mac = true
@@ -196,60 +171,15 @@ if (current_os == "win") {
 } else if (current_os == "android") {
   is_android = true
   is_chromeos = false
-  is_fnl = false
   is_ios = false
   is_linux = false
   is_mac = false
   is_nacl = false
   is_posix = true
   is_win = false
-} else if (current_os == "chromeos") {
-  is_android = false
-  is_chromeos = true
-  is_fnl = false
-  is_ios = false
-  is_linux = true
-  is_mac = false
-  is_nacl = false
-  is_posix = true
-  is_win = false
-} else if (current_os == "nacl") {
-  # current_os == "nacl" will be passed by the nacl toolchain definition.
-  # It is not set by default or on the command line. We treat is as a
-  # Posix variant.
-  is_android = false
-  is_chromeos = false
-  is_fnl = false
-  is_ios = false
-  is_linux = false
-  is_mac = false
-  is_nacl = true
-  is_posix = true
-  is_win = false
-} else if (current_os == "ios") {
-  is_android = false
-  is_chromeos = false
-  is_fnl = false
-  is_ios = true
-  is_linux = false
-  is_mac = false
-  is_nacl = false
-  is_posix = true
-  is_win = false
 } else if (current_os == "linux") {
   is_android = false
   is_chromeos = false
-  is_fnl = false
-  is_ios = false
-  is_linux = true
-  is_mac = false
-  is_nacl = false
-  is_posix = true
-  is_win = false
-} else if (current_os == "fnl") {
-  is_android = false
-  is_chromeos = false
-  is_fnl = true
   is_ios = false
   is_linux = true
   is_mac = false
@@ -258,119 +188,6 @@ if (current_os == "win") {
   is_win = false
 }
 
-# =============================================================================
-# SOURCES FILTERS
-# =============================================================================
-#
-# These patterns filter out platform-specific files when assigning to the
-# sources variable. The magic variable |sources_assignment_filter| is applied
-# to each assignment or appending to the sources variable and matches are
-# automatcally removed.
-#
-# Note that the patterns are NOT regular expressions. Only "*" and "\b" (path
-# boundary = end of string or slash) are supported, and the entire string
-# muct match the pattern (so you need "*.cc" to match all .cc files, for
-# example).
-
-# DO NOT ADD MORE PATTERNS TO THIS LIST, see set_sources_assignment_filter call
-# below.
-sources_assignment_filter = []
-if (!is_posix) {
-  sources_assignment_filter += [
-    "*_posix.h",
-    "*_posix.cc",
-    "*_posix_unittest.h",
-    "*_posix_unittest.cc",
-    "*\bposix/*",
-  ]
-}
-if (!is_win) {
-  sources_assignment_filter += [
-    "*_win.cc",
-    "*_win.h",
-    "*_win_unittest.cc",
-    "*\bwin/*",
-    "*.def",
-    "*.rc",
-  ]
-}
-if (!is_mac) {
-  sources_assignment_filter += [
-    "*_mac.h",
-    "*_mac.cc",
-    "*_mac.mm",
-    "*_mac_unittest.h",
-    "*_mac_unittest.cc",
-    "*_mac_unittest.mm",
-    "*\bmac/*",
-    "*_cocoa.h",
-    "*_cocoa.cc",
-    "*_cocoa.mm",
-    "*_cocoa_unittest.h",
-    "*_cocoa_unittest.cc",
-    "*_cocoa_unittest.mm",
-    "*\bcocoa/*",
-  ]
-}
-if (!is_ios) {
-  sources_assignment_filter += [
-    "*_ios.h",
-    "*_ios.cc",
-    "*_ios.mm",
-    "*_ios_unittest.h",
-    "*_ios_unittest.cc",
-    "*_ios_unittest.mm",
-    "*\bios/*",
-  ]
-}
-if (!is_mac && !is_ios) {
-  sources_assignment_filter += [ "*.mm" ]
-}
-if (!is_linux) {
-  sources_assignment_filter += [
-    "*_linux.h",
-    "*_linux.cc",
-    "*_linux_unittest.h",
-    "*_linux_unittest.cc",
-    "*\blinux/*",
-  ]
-}
-if (!is_android) {
-  sources_assignment_filter += [
-    "*_android.h",
-    "*_android.cc",
-    "*_android_unittest.h",
-    "*_android_unittest.cc",
-    "*\bandroid/*",
-  ]
-}
-if (!is_chromeos) {
-  sources_assignment_filter += [
-    "*_chromeos.h",
-    "*_chromeos.cc",
-    "*_chromeos_unittest.h",
-    "*_chromeos_unittest.cc",
-    "*\bchromeos/*",
-  ]
-}
-
-# DO NOT ADD MORE PATTERNS TO THIS LIST, see set_sources_assignment_filter call
-# below.
-
-# Actually save this list.
-#
-# These patterns are executed for every file in the source tree of every run.
-# Therefore, adding more patterns slows down the build for everybody. We should
-# only add automatic patterns for configurations affecting hundreds of files
-# across many projects in the tree.
-#
-# Therefore, we only add rules to this list corresponding to platforms on the
-# Chromium waterfall.  This is not for non-officially-supported platforms
-# (FreeBSD, etc.) toolkits, (X11, GTK, etc.), or features. For these cases,
-# write a conditional in the target to remove the file(s) from the list when
-# your platform/toolkit/feature doesn't apply.
-set_sources_assignment_filter(sources_assignment_filter)
-
 # =============================================================================
 # BUILD OPTIONS
 # =============================================================================
@@ -393,7 +210,6 @@ if (!is_clang && (is_asan || is_lsan || is_tsan || is_msan)) {
 # Holds all configs used for making native executables and libraries, to avoid
 # duplication in each target below.
 _native_compiler_configs = [
-  "//build/config:feature_flags",
   "//build/config/compiler:compiler",
   "//build/config/compiler:compiler_arm_fpu",
   "//build/config/compiler:chromium_code",
@@ -413,18 +229,13 @@ if (is_win) {
 if (is_posix) {
   _native_compiler_configs += [
     "//build/config/gcc:no_exceptions",
-    "//build/config/gcc:symbol_visibility_hidden",
   ]
 }
 
-if (is_fnl) {
-  _native_compiler_configs += [ "//build/config/fnl:sdk" ]
-} else if (is_linux) {
+if (is_linux) {
   _native_compiler_configs += [ "//build/config/linux:sdk" ]
 } else if (is_mac) {
   _native_compiler_configs += [ "//build/config/mac:sdk" ]
-} else if (is_ios) {
-  _native_compiler_configs += [ "//build/config/ios:sdk" ]
 } else if (is_android) {
   _native_compiler_configs += [ "//build/config/android:sdk" ]
 }
@@ -440,36 +251,18 @@ if (is_clang) {
 if (is_debug) {
   _native_compiler_configs += [ "//build/config:debug" ]
   _default_optimization_config = "//build/config/compiler:no_optimize"
-} else {
+} else if (is_release) {
   _native_compiler_configs += [ "//build/config:release" ]
   _default_optimization_config = "//build/config/compiler:optimize"
+} else {
+  assert(is_product)
+  _native_compiler_configs += [ "//build/config:product" ]
+  _default_optimization_config = "//build/config/compiler:optimize"
 }
 _native_compiler_configs += [ _default_optimization_config ]
 
-# If it wasn't manually set, set to an appropriate default.
-if (symbol_level == -1) {
-  # Linux is slowed by having symbols as part of the target binary, whereas
-  # Mac and Windows have them separate, so in Release Linux, default them off.
-  if (is_debug || !is_linux) {
-    symbol_level = 2
-  } else if (is_asan || is_lsan || is_tsan || is_msan) {
-    # Sanitizers require symbols for filename suppressions to work.
-    symbol_level = 1
-  } else {
-    symbol_level = 0
-  }
-}
-
 # Symbol setup.
-if (symbol_level == 2) {
-  _default_symbols_config = "//build/config/compiler:symbols"
-} else if (symbol_level == 1) {
-  _default_symbols_config = "//build/config/compiler:minimal_symbols"
-} else if (symbol_level == 0) {
-  _default_symbols_config = "//build/config/compiler:no_symbols"
-} else {
-  assert(false, "Bad value for symbol_level.")
-}
+_default_symbols_config = "//build/config/compiler:symbols"
 _native_compiler_configs += [ _default_symbols_config ]
 
 # Windows linker setup for EXEs and DLLs.
@@ -486,8 +279,7 @@ if (is_win) {
 }
 
 # Executable defaults.
-_executable_configs =
-    _native_compiler_configs + [ "//build/config:default_libs" ]
+_executable_configs = _native_compiler_configs
 if (is_win) {
   _executable_configs += _windows_linker_configs
 } else if (is_mac) {
@@ -511,8 +303,7 @@ set_defaults("static_library") {
 }
 
 # Shared library defaults (also for components in component mode).
-_shared_library_configs =
-    _native_compiler_configs + [ "//build/config:default_libs" ]
+_shared_library_configs = _native_compiler_configs
 if (is_win) {
   _shared_library_configs += _windows_linker_configs
 } else if (is_mac) {
@@ -526,29 +317,13 @@ if (is_win) {
 set_defaults("shared_library") {
   configs = _shared_library_configs
 }
-if (is_component_build) {
-  set_defaults("component") {
-    configs = _shared_library_configs
-  }
-}
 
 # Source set defaults (also for components in non-component mode).
 set_defaults("source_set") {
   configs = _native_compiler_configs
 }
-if (!is_component_build) {
-  set_defaults("component") {
-    configs = _native_compiler_configs
-  }
-}
-
-# Test defaults.
-set_defaults("test") {
-  if (is_android) {
-    configs = _shared_library_configs
-  } else {
-    configs = _executable_configs
-  }
+set_defaults("component") {
+  configs = _native_compiler_configs
 }
 
 # ==============================================================================
@@ -570,7 +345,6 @@ if (is_win) {
   set_default_toolchain("$host_toolchain")
 } else if (is_android) {
   if (host_os == "linux") {
-    # Use clang for the x86/64 Linux host builds.
     if (host_cpu == "x86" || host_cpu == "x64") {
       host_toolchain = "//build/toolchain/linux:clang_$host_cpu"
     } else {
@@ -594,234 +368,108 @@ if (is_win) {
     host_toolchain = "//build/toolchain/linux:$host_cpu"
     set_default_toolchain("//build/toolchain/linux:$current_cpu")
   }
-  if (is_chromeos && cros_use_custom_toolchain) {
-    set_default_toolchain("//build/toolchain/cros:target")
-  }
-  if (is_fnl) {
-    set_default_toolchain("//build/toolchain/fnl:target")
-  }
 } else if (is_mac) {
   host_toolchain = "//build/toolchain/mac:clang_x64"
   set_default_toolchain(host_toolchain)
-} else if (is_ios) {
-  host_toolchain = "//build/toolchain/mac:clang_x64"
-  if (use_ios_simulator) {
-    set_default_toolchain("//build/toolchain/mac:ios_clang_x64")
-  } else {
-    set_default_toolchain("//build/toolchain/mac:ios_clang_arm")
-  }
-} else if (is_nacl) {
-  # TODO(GYP): This will need to change when we get NaCl working
-  # on multiple platforms, but this whole block of code (how we define
-  # host_toolchain) needs to be reworked regardless to key off of host_os
-  # and host_cpu rather than the is_* variables.
-  host_toolchain = "//build/toolchain/linux:clang_x64"
 }
 
 # ==============================================================================
 # COMPONENT SETUP
 # ==============================================================================
 
-# TODO(brettw) erase this once the built-in "component" function is removed.
-if (is_component_build) {
-  component_mode = "shared_library"
-} else {
-  component_mode = "source_set"
-}
+# Don't try to do component builds for the standalone Dart VM.
+assert(!is_component_build)
+component_mode = "source_set"
 
 template("component") {
-  if (is_component_build) {
-    shared_library(target_name) {
-      # Configs will always be defined since we set_defaults for a component
-      # above. We want to use those rather than whatever came with the nested
-      # shared/static library inside the component.
-      configs = []  # Prevent list overwriting warning.
-      configs = invoker.configs
+  source_set(target_name) {
+    # See above.
+    configs = []  # Prevent list overwriting warning.
+    configs = invoker.configs
 
-      # The sources assignment filter will have already been applied when the
-      # code was originally executed. We don't want to apply it again, since
-      # the original target may have override it for some assignments.
-      set_sources_assignment_filter([])
+    # See above call.
+    set_sources_assignment_filter([])
 
-      if (defined(invoker.all_dependent_configs)) {
-        all_dependent_configs = invoker.all_dependent_configs
-      }
-      if (defined(invoker.allow_circular_includes_from)) {
-        allow_circular_includes_from = invoker.allow_circular_includes_from
-      }
-      if (defined(invoker.cflags)) {
-        cflags = invoker.cflags
-      }
-      if (defined(invoker.cflags_c)) {
-        cflags_c = invoker.cflags_c
-      }
-      if (defined(invoker.cflags_cc)) {
-        cflags_cc = invoker.cflags_cc
-      }
-      if (defined(invoker.cflags_objc)) {
-        cflags_objc = invoker.cflags_objc
-      }
-      if (defined(invoker.cflags_objcc)) {
-        cflags_objcc = invoker.cflags_objcc
-      }
-      if (defined(invoker.check_includes)) {
-        check_includes = invoker.check_includes
-      }
-      if (defined(invoker.data)) {
-        data = invoker.data
-      }
-      if (defined(invoker.data_deps)) {
-        data_deps = invoker.data_deps
-      }
-      if (defined(invoker.datadeps)) {
-        datadeps = invoker.datadeps
-      }
-      if (defined(invoker.defines)) {
-        defines = invoker.defines
-      }
-
-      # All shared libraries must have the sanitizer deps to properly link in
-      # asan mode (this target will be empty in other cases).
-      if (defined(invoker.deps)) {
-        deps = invoker.deps + [ "//build/config/sanitizers:deps" ]
-      } else {
-        deps = [
-          "//build/config/sanitizers:deps",
-        ]
-      }
-      if (defined(invoker.direct_dependent_configs)) {
-        direct_dependent_configs = invoker.direct_dependent_configs
-      }
-      if (defined(invoker.forward_dependent_configs_from)) {
-        forward_dependent_configs_from = invoker.forward_dependent_configs_from
-      }
-      if (defined(invoker.include_dirs)) {
-        include_dirs = invoker.include_dirs
-      }
-      if (defined(invoker.ldflags)) {
-        ldflags = invoker.ldflags
-      }
-      if (defined(invoker.lib_dirs)) {
-        lib_dirs = invoker.lib_dirs
-      }
-      if (defined(invoker.libs)) {
-        libs = invoker.libs
-      }
-      if (defined(invoker.output_extension)) {
-        output_extension = invoker.output_extension
-      }
-      if (defined(invoker.output_name)) {
-        output_name = invoker.output_name
-      }
-      if (defined(invoker.public)) {
-        public = invoker.public
-      }
-      if (defined(invoker.public_configs)) {
-        public_configs = invoker.public_configs
-      }
-      if (defined(invoker.public_deps)) {
-        public_deps = invoker.public_deps
-      }
-      if (defined(invoker.sources)) {
-        sources = invoker.sources
-      }
-      if (defined(invoker.testonly)) {
-        testonly = invoker.testonly
-      }
-      if (defined(invoker.visibility)) {
-        visibility = invoker.visibility
-      }
+    if (defined(invoker.all_dependent_configs)) {
+      all_dependent_configs = invoker.all_dependent_configs
     }
-  } else {
-    source_set(target_name) {
-      # See above.
-      configs = []  # Prevent list overwriting warning.
-      configs = invoker.configs
-
-      # See above call.
-      set_sources_assignment_filter([])
-
-      if (defined(invoker.all_dependent_configs)) {
-        all_dependent_configs = invoker.all_dependent_configs
-      }
-      if (defined(invoker.allow_circular_includes_from)) {
-        allow_circular_includes_from = invoker.allow_circular_includes_from
-      }
-      if (defined(invoker.cflags)) {
-        cflags = invoker.cflags
-      }
-      if (defined(invoker.cflags_c)) {
-        cflags_c = invoker.cflags_c
-      }
-      if (defined(invoker.cflags_cc)) {
-        cflags_cc = invoker.cflags_cc
-      }
-      if (defined(invoker.cflags_objc)) {
-        cflags_objc = invoker.cflags_objc
-      }
-      if (defined(invoker.cflags_objcc)) {
-        cflags_objcc = invoker.cflags_objcc
-      }
-      if (defined(invoker.check_includes)) {
-        check_includes = invoker.check_includes
-      }
-      if (defined(invoker.data)) {
-        data = invoker.data
-      }
-      if (defined(invoker.data_deps)) {
-        data_deps = invoker.data_deps
-      }
-      if (defined(invoker.datadeps)) {
-        datadeps = invoker.datadeps
-      }
-      if (defined(invoker.defines)) {
-        defines = invoker.defines
-      }
-      if (defined(invoker.deps)) {
-        deps = invoker.deps
-      }
-      if (defined(invoker.direct_dependent_configs)) {
-        direct_dependent_configs = invoker.direct_dependent_configs
-      }
-      if (defined(invoker.forward_dependent_configs_from)) {
-        forward_dependent_configs_from = invoker.forward_dependent_configs_from
-      }
-      if (defined(invoker.include_dirs)) {
-        include_dirs = invoker.include_dirs
-      }
-      if (defined(invoker.ldflags)) {
-        ldflags = invoker.ldflags
-      }
-      if (defined(invoker.lib_dirs)) {
-        lib_dirs = invoker.lib_dirs
-      }
-      if (defined(invoker.libs)) {
-        libs = invoker.libs
-      }
-      if (defined(invoker.output_extension)) {
-        output_extension = invoker.output_extension
-      }
-      if (defined(invoker.output_name)) {
-        output_name = invoker.output_name
-      }
-      if (defined(invoker.public)) {
-        public = invoker.public
-      }
-      if (defined(invoker.public_configs)) {
-        public_configs = invoker.public_configs
-      }
-      if (defined(invoker.public_deps)) {
-        public_deps = invoker.public_deps
-      }
-      if (defined(invoker.sources)) {
-        sources = invoker.sources
-      }
-      if (defined(invoker.testonly)) {
-        testonly = invoker.testonly
-      }
-      if (defined(invoker.visibility)) {
-        visibility = invoker.visibility
-      }
+    if (defined(invoker.allow_circular_includes_from)) {
+      allow_circular_includes_from = invoker.allow_circular_includes_from
+    }
+    if (defined(invoker.cflags)) {
+      cflags = invoker.cflags
+    }
+    if (defined(invoker.cflags_c)) {
+      cflags_c = invoker.cflags_c
+    }
+    if (defined(invoker.cflags_cc)) {
+      cflags_cc = invoker.cflags_cc
+    }
+    if (defined(invoker.cflags_objc)) {
+      cflags_objc = invoker.cflags_objc
+    }
+    if (defined(invoker.cflags_objcc)) {
+      cflags_objcc = invoker.cflags_objcc
+    }
+    if (defined(invoker.check_includes)) {
+      check_includes = invoker.check_includes
+    }
+    if (defined(invoker.data)) {
+      data = invoker.data
+    }
+    if (defined(invoker.data_deps)) {
+      data_deps = invoker.data_deps
+    }
+    if (defined(invoker.datadeps)) {
+      datadeps = invoker.datadeps
+    }
+    if (defined(invoker.defines)) {
+      defines = invoker.defines
+    }
+    if (defined(invoker.deps)) {
+      deps = invoker.deps
+    }
+    if (defined(invoker.direct_dependent_configs)) {
+      direct_dependent_configs = invoker.direct_dependent_configs
+    }
+    if (defined(invoker.forward_dependent_configs_from)) {
+      forward_dependent_configs_from = invoker.forward_dependent_configs_from
+    }
+    if (defined(invoker.include_dirs)) {
+      include_dirs = invoker.include_dirs
+    }
+    if (defined(invoker.ldflags)) {
+      ldflags = invoker.ldflags
+    }
+    if (defined(invoker.lib_dirs)) {
+      lib_dirs = invoker.lib_dirs
+    }
+    if (defined(invoker.libs)) {
+      libs = invoker.libs
+    }
+    if (defined(invoker.output_extension)) {
+      output_extension = invoker.output_extension
+    }
+    if (defined(invoker.output_name)) {
+      output_name = invoker.output_name
+    }
+    if (defined(invoker.public)) {
+      public = invoker.public
+    }
+    if (defined(invoker.public_configs)) {
+      public_configs = invoker.public_configs
+    }
+    if (defined(invoker.public_deps)) {
+      public_deps = invoker.public_deps
+    }
+    if (defined(invoker.sources)) {
+      sources = invoker.sources
+    }
+    if (defined(invoker.testonly)) {
+      testonly = invoker.testonly
+    }
+    if (defined(invoker.visibility)) {
+      visibility = invoker.visibility
     }
   }
 }
diff --git a/build/config/allocator.gni b/build/config/allocator.gni
deleted file mode 100644
index 71418a8e772..00000000000
--- a/build/config/allocator.gni
+++ /dev/null
@@ -1,16 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# TODO(GYP): Make tcmalloc work on win.
-if (is_android || current_cpu == "mipsel" || is_mac || is_ios || is_asan ||
-    is_lsan || is_tsan || is_msan || is_win) {
-  _default_allocator = "none"
-} else {
-  _default_allocator = "tcmalloc"
-}
-
-declare_args() {
-  # Memory allocator to use. Set to "none" to use default allocator.
-  use_allocator = _default_allocator
-}
diff --git a/build/config/android/config.gni b/build/config/android/config.gni
index 5457b889efd..a16407bbfc7 100644
--- a/build/config/android/config.gni
+++ b/build/config/android/config.gni
@@ -51,10 +51,8 @@ if (is_android) {
 
   # Defines the name the Android build gives to the current host CPU
   # architecture, which is different than the names GN uses.
-  if (host_cpu == "x64") {
+  if ((host_cpu == "x64") || (host_cpu == "x86")) {
     android_host_arch = "x86_64"
-  } else if (host_cpu == "x86") {
-    android_host_arch = "x86"
   } else {
     assert(false, "Need Android toolchain support for your build CPU arch.")
   }
diff --git a/build/config/chrome_build.gni b/build/config/chrome_build.gni
deleted file mode 100644
index c2132c4a162..00000000000
--- a/build/config/chrome_build.gni
+++ /dev/null
@@ -1,19 +0,0 @@
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-declare_args() {
-  # Selects the desired build flavor. Official builds get additional
-  # processing to prepare for release. Normally you will want to develop and
-  # test with this flag off.
-  is_official_build = false
-
-  # Select the desired branding flavor. False means normal Chromium branding,
-  # true means official Google Chrome branding (requires extra Google-internal
-  # resources).
-  is_chrome_branded = false
-
-  # Break chrome.dll into multple pieces based on process type. Only available
-  # on Windows.
-  is_multi_dll_chrome = is_win && !is_component_build
-}
diff --git a/build/config/clang/clang.gni b/build/config/clang/clang.gni
index cb84879466f..3893ca38a3b 100644
--- a/build/config/clang/clang.gni
+++ b/build/config/clang/clang.gni
@@ -5,5 +5,5 @@
 declare_args() {
   # Indicates if the build should use the Chrome-specific plugins for enforcing
   # coding guidelines, etc. Only used when compiling with Clang.
-  clang_use_chrome_plugins = is_clang && !is_nacl
+  clang_use_chrome_plugins = false
 }
diff --git a/build/config/compiler/BUILD.gn b/build/config/compiler/BUILD.gn
index 04d4bd9c5f5..778a27a380d 100644
--- a/build/config/compiler/BUILD.gn
+++ b/build/config/compiler/BUILD.gn
@@ -3,7 +3,6 @@
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
-import("//build/config/chrome_build.gni")
 if (current_cpu == "arm") {
   import("//build/config/arm.gni")
 }
@@ -21,39 +20,6 @@ import("//build/toolchain/ccache.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 
 declare_args() {
-  # Normally, Android builds are lightly optimized, even for debug builds, to
-  # keep binary size down. Setting this flag to true disables such optimization
-  android_full_debug = false
-
-  # Whether to use the binary binutils checked into third_party/binutils.
-  # These are not multi-arch so cannot be used except on x86 and x86-64 (the
-  # only two architectures that are currently checked in). Turn this off when
-  # you are using a custom toolchain and need to control -B in cflags.
-  linux_use_bundled_binutils = is_linux && current_cpu == "x64"
-
-  # Compile in such a way as to enable profiling of the generated code. For
-  # example, don't omit the frame pointer and leave in symbols.
-  enable_profiling = false
-
-  # Compile in such a way as to make it possible for the profiler to unwind full
-  # stack frames. Setting this flag has a large effect on the performance of the
-  # generated code than just setting profiling, but gives the profiler more
-  # information to analyze.
-  # Requires profiling to be set to true.
-  enable_full_stack_frames_for_profiling = false
-
-  # Use gold for linking on 64-bit Linux only (on 32-bit it runs out of
-  # address space, and it doesn't support cross-compiling).
-  use_gold = is_linux && current_cpu == "x64"
-
-  # use_debug_fission: whether to use split DWARF debug info
-  # files. This can reduce link time significantly, but is incompatible
-  # with some utilities such as icecc and ccache. Requires gold and
-  # gcc >= 4.8 or clang.
-  # http://gcc.gnu.org/wiki/DebugFission
-  use_debug_fission = is_debug && !is_win && use_gold &&
-                      linux_use_bundled_binutils && !use_ccache
-
   if (is_win) {
     # Whether the VS xtree header has been patched to disable warning 4702. If
     # it has, then we don't need to disable 4702 (unreachable code warning).
@@ -143,7 +109,6 @@ config("compiler") {
   } else {
     # Common GCC compiler flags setup.
     # --------------------------------
-    cflags += [ "-fno-strict-aliasing" ]  # See http://crbug.com/32204
     common_flags = [
       # Not exporting C++ inline functions can generally be applied anywhere
       # so we do so here. Normal function visibility is controlled by
@@ -153,18 +118,8 @@ config("compiler") {
     cflags_cc += common_flags
     cflags_objcc += common_flags
 
-    # Stack protection.
-    if (is_mac) {
-      cflags += [ "-fstack-protector-all" ]
-    } else if (is_linux) {
-      cflags += [
-        "-fstack-protector",
-        "--param=ssp-buffer-size=4",
-      ]
-    }
-
     # Linker warnings.
-    if (!(is_chromeos && current_cpu == "arm") && !is_mac && !is_ios) {
+    if ((current_cpu != "arm") && !is_mac) {
       # TODO(jochen): Enable this on chromeos on arm. http://crbug.com/356580
       ldflags += [ "-Wl,--fatal-warnings" ]
     }
@@ -217,11 +172,6 @@ config("compiler") {
         "//buildtools/third_party/libc++abi/trunk/include",
       ]
     }
-
-    if (is_fnl) {
-      # TODO(kulakowski) remove when fnl no longer uses gcc
-      cflags += [ "-Wno-maybe-uninitialized" ]
-    }
   }
 
   if (is_clang && is_debug) {
@@ -237,7 +187,7 @@ config("compiler") {
     cflags_objcc += extra_flags
   }
 
-  if (is_clang && !is_nacl) {
+  if (is_clang) {
     # This is here so that all files get recompiled after a clang roll and
     # when turning clang on or off. (defines are passed via the command line,
     # and build system rebuild things when their commandline changes). Nothing
@@ -250,7 +200,7 @@ config("compiler") {
 
   # Mac-specific compiler flags setup.
   # ----------------------------------
-  if (is_mac || is_ios) {
+  if (is_mac) {
     # These flags are shared between the C compiler and linker.
     common_mac_flags = []
 
@@ -310,6 +260,7 @@ config("compiler") {
         ]
       }
     } else if (current_cpu == "arm") {
+
       cflags += [
         "-march=$arm_arch",
         "-mfloat-abi=$arm_float_abi",
@@ -388,45 +339,7 @@ config("compiler") {
       }
     }
 
-    defines += [ "_FILE_OFFSET_BITS=64" ]
-
-    if (!is_android) {
-      defines += [
-        "_LARGEFILE_SOURCE",
-        "_LARGEFILE64_SOURCE",
-      ]
-    }
-
-    # Omit unwind support in official builds to save space. We can use breakpad
-    # for these builds.
-    if (is_chrome_branded && is_official_build) {
-      cflags += [
-        "-fno-unwind-tables",
-        "-fno-asynchronous-unwind-tables",
-      ]
-      defines += [ "NO_UNWIND_TABLES" ]
-    } else {
-      cflags += [ "-funwind-tables" ]
-    }
-  }
-
-  if (enable_profiling && !is_debug) {
-    # The GYP build spams this define into every compilation unit, as we do
-    # here, but it only appears to be used in base and a couple other places.
-    # TODO(abarth): Should we move this define closer to where it's used?
-    defines += [ "ENABLE_PROFILING" ]
-
-    cflags += [
-      "-fno-omit-frame-pointer",
-      "-g",
-    ]
-
-    if (enable_full_stack_frames_for_profiling) {
-      cflags += [
-        "-fno-inline",
-        "-fno-optimize-sibling-calls",
-      ]
-    }
+    cflags += [ "-funwind-tables" ]
   }
 
   # Linux/Android common flags setup.
@@ -434,7 +347,6 @@ config("compiler") {
   if (is_linux || is_android) {
     cflags += [
       "-fPIC",
-      "-pipe",  # Use pipes for communicating between sub-processes. Faster.
     ]
 
     ldflags += [
@@ -443,9 +355,6 @@ config("compiler") {
       "-Wl,-z,now",
       "-Wl,-z,relro",
     ]
-    if (!using_sanitizer) {
-      ldflags += [ "-Wl,-z,defs" ]
-    }
   }
 
   # Linux-specific compiler flags setup.
@@ -454,46 +363,6 @@ config("compiler") {
     cflags += [ "-pthread" ]
     ldflags += [ "-pthread" ]
   }
-  if (use_gold) {
-    gold_path = rebase_path("//third_party/binutils/Linux_x64/Release/bin",
-                            root_build_dir)
-    ldflags += [
-      "-B$gold_path",
-
-      # Newer gccs and clangs support -fuse-ld, use the flag to force gold
-      # selection.
-      # gcc -- http://gcc.gnu.org/onlinedocs/gcc-4.8.0/gcc/Optimize-Options.html
-      "-fuse-ld=gold",
-
-      # Experimentation found that using four linking threads
-      # saved ~20% of link time.
-      # https://groups.google.com/a/chromium.org/group/chromium-dev/browse_thread/thread/281527606915bb36
-      # Only apply this to the target linker, since the host
-      # linker might not be gold, but isn't used much anyway.
-      # TODO(raymes): Disable threading because gold is frequently
-      # crashing on the bots: crbug.com/161942.
-      #"-Wl,--threads",
-      #"-Wl,--thread-count=4",
-    ]
-
-    if (!is_asan && !is_msan && !is_lsan && !is_tsan) {
-      # TODO(brettw) common.gypi has this only for target toolset.
-      ldflags += [ "-Wl,--icf=all" ]
-    }
-
-    # TODO(thestig): Make this flag work with GN.
-    #if (!is_official_build && !is_chromeos && !(is_asan || is_lsan || is_tsan || is_msan)) {
-    #  ldflags += [
-    #    "-Wl,--detect-odr-violations",
-    #  ]
-    #}
-  }
-
-  if (linux_use_bundled_binutils) {
-    binutils_path = rebase_path("//third_party/binutils/Linux_x64/Release/bin",
-                                root_build_dir)
-    cflags += [ "-B$binutils_path" ]
-  }
 
   # Clang-specific compiler flags setup.
   # ------------------------------------
@@ -501,20 +370,6 @@ config("compiler") {
     cflags += [ "-fcolor-diagnostics" ]
   }
 
-  # C++11 compiler flags setup.
-  # ---------------------------
-  if (is_linux || is_android || is_nacl) {
-    # gnu++11 instead of c++11 is needed because some code uses typeof() (a
-    # GNU extension).
-    # TODO(thakis): Eventually switch this to c++11 instead,
-    # http://crbug.com/427584
-    cflags_cc += [ "-std=gnu++11" ]
-  } else if (!is_win) {
-    cc_std = [ "-std=c++11" ]
-    cflags_cc += cc_std
-    cflags_objcc += cc_std
-  }
-
   # Android-specific flags setup.
   # -----------------------------
   if (is_android) {
@@ -552,17 +407,10 @@ config("compiler") {
     }
 
     ldflags += [
-      "-Wl,--no-undefined",
-
       # Don't allow visible symbols from libgcc or libc++ to be
       # re-exported.
       "-Wl,--exclude-libs=libgcc.a",
       "-Wl,--exclude-libs=libc++_static.a",
-
-      # Don't allow visible symbols from libraries that contain
-      # assembly code with symbols that aren't hidden properly.
-      # http://crbug.com/448386
-      "-Wl,--exclude-libs=libvpx_assembly_arm.a",
     ]
     if (current_cpu == "arm") {
       ldflags += [
@@ -584,7 +432,7 @@ config("compiler") {
 }
 
 config("compiler_arm_fpu") {
-  if (current_cpu == "arm" && !is_ios) {
+  if (current_cpu == "arm") {
     cflags = [ "-mfpu=$arm_fpu" ]
   }
 }
@@ -833,19 +681,11 @@ if (is_win) {
     # TODO(abarth): Re-enable once https://github.com/domokit/mojo/issues/728
     #               is fixed.
     # default_warning_flags += [ "-Wnewline-eof" ]
-    if (!is_nacl) {
-      # When compiling Objective-C, warns if a method is used whose
-      # availability is newer than the deployment target. This is not
-      # required when compiling Chrome for iOS.
-      default_warning_flags += [ "-Wpartial-availability" ]
-    }
-  }
 
-  if (gcc_version >= 48) {
-    default_warning_flags_cc += [
-      # See comment for -Wno-c++11-narrowing.
-      "-Wno-narrowing",
-    ]
+    # When compiling Objective-C, warns if a method is used whose
+    # availability is newer than the deployment target. This is not
+    # required when compiling Chrome for iOS.
+    default_warning_flags += [ "-Wpartial-availability" ]
   }
 
   # Suppress warnings about ABI changes on ARM (Clang doesn't give this
@@ -883,43 +723,6 @@ if (is_win) {
     default_warning_flags += [ "-Wno-unused-local-typedefs" ]
   }
 }
-if (is_clang) {
-  default_warning_flags += [
-    # This warns on using ints as initializers for floats in
-    # initializer lists (e.g. |int a = f(); CGSize s = { a, a };|),
-    # which happens in several places in chrome code. Not sure if
-    # this is worth fixing.
-    "-Wno-c++11-narrowing",
-
-    # Don't die on dtoa code that uses a char as an array index.
-    # This is required solely for base/third_party/dmg_fp/dtoa.cc.
-    # TODO(brettw) move this to that project then!
-    "-Wno-char-subscripts",
-
-    # Warns on switches on enums that cover all enum values but
-    # also contain a default: branch. Chrome is full of that.
-    "-Wno-covered-switch-default",
-
-    # Clang considers the `register` keyword as deprecated, but e.g.
-    # code generated by flex (used in angle) contains that keyword.
-    # http://crbug.com/255186
-    "-Wno-deprecated-register",
-  ]
-
-  # NaCl's Clang compiler and Chrome's hermetic Clang compiler will almost
-  # always have different versions. Certain flags may not be recognized by
-  # one version or the other.
-  if (!is_nacl) {
-    # Flags NaCl does not recognize.
-    default_warning_flags += [
-      # TODO(hans): Get this cleaned up, http://crbug.com/428099
-      "-Wno-inconsistent-missing-override",
-
-      # TODO(thakis): Enable this, crbug.com/507717
-      "-Wno-shift-negative-value",
-    ]
-  }
-}
 
 # chromium_code ---------------------------------------------------------------
 #
@@ -935,14 +738,8 @@ config("chromium_code") {
       "-Wextra",
     ]
 
-    # In Chromium code, we define __STDC_foo_MACROS in order to get the
-    # C99 macros on Mac and Linux.
-    defines = [
-      "__STDC_CONSTANT_MACROS",
-      "__STDC_FORMAT_MACROS",
-    ]
-
-    if (!using_sanitizer && (!is_linux || !is_clang || is_official_build)) {
+    defines = []
+    if (!using_sanitizer && (!is_linux || !is_clang)) {
       # _FORTIFY_SOURCE isn't really supported by Clang now, see
       # http://llvm.org/bugs/show_bug.cgi?id=16821.
       # It seems to work fine with Ubuntu 12 headers though, so use it in
@@ -975,37 +772,6 @@ config("no_chromium_code") {
     ]
   }
 
-  if (is_linux) {
-    # Don't warn about ignoring the return value from e.g. close(). This is
-    # off by default in some gccs but on by default in others. BSD systems do
-    # not support this option, since they are usually using gcc 4.2.1, which
-    # does not have this flag yet.
-    cflags += [ "-Wno-unused-result" ]
-  }
-
-  if (is_clang) {
-    cflags += [
-      # TODO(mgiuca): Move this suppression into individual third-party
-      # libraries as required. http://crbug.com/505301.
-      "-Wno-overloaded-virtual",
-
-      # Lots of third-party libraries have unused variables. Instead of
-      # suppressing them individually, we just blanket suppress them here.
-      "-Wno-unused-variable",
-    ]
-  }
-
-  if (is_linux || is_android) {
-    cflags += [
-      # Don't warn about printf format problems. This is off by default in gcc
-      # but on in Ubuntu's gcc(!).
-      "-Wno-format",
-    ]
-    cflags_cc += [
-      # Don't warn about hash_map in third-party code.
-      "-Wno-deprecated",
-    ]
-  }
   cflags += default_warning_flags
   cflags_cc += default_warning_flags_cc
 }
@@ -1029,34 +795,6 @@ config("no_rtti") {
   }
 }
 
-# Warnings ---------------------------------------------------------------------
-
-# This will generate warnings when using Clang if code generates exit-time
-# destructors, which will slow down closing the program.
-# TODO(thakis): Make this a blacklist instead, http://crbug.com/101600
-config("wexit_time_destructors") {
-  # TODO: Enable on Windows too, http://crbug.com/404525
-  if (is_clang && !is_win) {
-    cflags = [ "-Wexit-time-destructors" ]
-  }
-}
-
-# On Windows compiling on x64, VC will issue a warning when converting
-# size_t to int because it will truncate the value. Our code should not have
-# these warnings and one should use a static_cast or a checked_cast for the
-# conversion depending on the case. However, a lot of code still needs to be
-# fixed. Apply this config to such targets to disable the warning.
-#
-# Note that this can be applied regardless of platform and architecture to
-# clean up the call sites. This will only apply the flag when necessary.
-#
-# TODO(jschuh): crbug.com/167187 fix this and delete this config.
-config("no_size_t_to_int_warning") {
-  if (is_win && current_cpu == "x64") {
-    cflags = [ "/wd4267" ]
-  }
-}
-
 # Optimization -----------------------------------------------------------------
 #
 # Note that BUILDCONFIG.gn sets up a variable "default_optimization_config"
@@ -1066,9 +804,9 @@ config("no_size_t_to_int_warning") {
 # add back the one you want to override it with:
 #
 #   configs -= default_optimization_config
-#   configs += [ "//build/config/compiler/optimize_max" ]
+#   configs += [ ":optimize_max" ]
 
-# Shared settings for both "optimize" and "optimize_max" configs.
+# Shared settings.
 # IMPORTANT: On Windows "/O1" and "/O2" must go before the common flags.
 if (is_win) {
   common_optimize_on_cflags = [
@@ -1100,25 +838,15 @@ if (is_win) {
   common_optimize_on_ldflags = []
 
   if (is_android) {
-    if (!using_sanitizer) {
-      common_optimize_on_cflags += [ "-fomit-frame-pointer" ]
-    }
-
-    # TODO(jdduke) Re-enable on mips after resolving linking
-    # issues with libc++ (crbug.com/456380).
-    if (current_cpu != "mipsel" && current_cpu != "mips64el") {
-      common_optimize_on_ldflags += [
-        # Warn in case of text relocations.
-        "-Wl,--warn-shared-textrel",
-      ]
-    }
+    common_optimize_on_ldflags += [
+      # Warn in case of text relocations.
+      "-Wl,--warn-shared-textrel",
+    ]
   }
 
-  if (is_mac || is_ios) {
-    if (symbol_level == 2) {
-      # Mac dead code stripping requires symbols.
-      common_optimize_on_ldflags += [ "-Wl,-dead_strip" ]
-    }
+  if (is_mac) {
+    # Mac dead code stripping requires symbols.
+    common_optimize_on_ldflags += [ "-Wl,-dead_strip" ]
   } else {
     # Non-Mac Posix linker flags.
     common_optimize_on_ldflags += [
@@ -1143,10 +871,10 @@ config("optimize") {
     # Favor size over speed, /O1 must be before the common flags. The GYP
     # build also specifies /Os and /GF but these are implied by /O1.
     cflags = [ "/O1" ] + common_optimize_on_cflags + [ "/Oi" ]
-  } else if (is_android || is_ios) {
+  } else if (is_android) {
     cflags = [ "-Os" ] + common_optimize_on_cflags  # Favor size over speed.
   } else {
-    cflags = [ "-O2" ] + common_optimize_on_cflags
+    cflags = [ "-O3" ] + common_optimize_on_cflags
   }
   ldflags = common_optimize_on_ldflags
 }
@@ -1159,7 +887,7 @@ config("no_optimize") {
       "/Ob0",  # Disable all inlining (on by default).
       "/RTC1",  # Runtime checks for stack frame and uninitialized variables.
     ]
-  } else if (is_android && !android_full_debug) {
+  } else if (is_android) {
     # On Android we kind of optimize some things that don't affect debugging
     # much even when optimization is disabled to get the binary size down.
     cflags = [
@@ -1167,41 +895,9 @@ config("no_optimize") {
       "-fdata-sections",
       "-ffunction-sections",
     ]
-    if (!using_sanitizer) {
-      cflags += [ "-fomit-frame-pointer" ]
-    }
     ldflags = common_optimize_on_ldflags
   } else {
-    cflags = [ "-O0" ]
-  }
-}
-
-# Turns up the optimization level. On Windows, this implies whole program
-# optimization and link-time code generation which is very expensive and should
-# be used sparingly.
-config("optimize_max") {
-  ldflags = common_optimize_on_ldflags
-  if (is_win) {
-    # Favor speed over size, /O2 must be before the common flags. The GYP
-    # build also specifies /Ot, /Oi, and /GF, but these are implied by /O2.
-    cflags = [ "/O2" ] + common_optimize_on_cflags
-    if (is_official_build) {
-      # TODO(GYP): TODO(dpranke): Should these only be on in an official
-      # build, or on all the time? For now we'll require official build so
-      # that the compile is clean.
-      cflags += [
-        "/GL",  # Whole program optimization.
-
-        # Disable Warning 4702 ("Unreachable code") for the WPO/PGO builds.
-        # Probably anything that this would catch that wouldn't be caught in a
-        # normal build isn't going to actually be a bug, so the incremental
-        # value of C4702 for PGO builds is likely very small.
-        "/wd4702",
-      ]
-      ldflags += [ "/LTCG" ]
-    }
-  } else {
-    cflags = [ "-O2" ] + common_optimize_on_cflags
+    cflags = [ "-O1" ]
   }
 }
 
@@ -1217,27 +913,9 @@ config("symbols") {
     }
     ldflags = [ "/DEBUG" ]
   } else {
-    cflags = [ "-g2" ]
-    if (use_debug_fission) {
-      cflags += [ "-gsplit-dwarf" ]
-    }
-  }
-}
-
-config("minimal_symbols") {
-  if (is_win) {
-    # Linker symbols for backtraces only.
-    ldflags = [ "/DEBUG" ]
-  } else {
-    cflags = [ "-g1" ]
-    if (use_debug_fission) {
-      cflags += [ "-gsplit-dwarf" ]
-    }
-  }
-}
-
-config("no_symbols") {
-  if (!is_win) {
-    cflags = [ "-g0" ]
+    cflags = [
+      "-g3",
+      "-ggdb3",
+    ]
   }
 }
diff --git a/build/config/crypto.gni b/build/config/crypto.gni
deleted file mode 100644
index 2cd72d338ca..00000000000
--- a/build/config/crypto.gni
+++ /dev/null
@@ -1,29 +0,0 @@
-# Copyright (c) 2013 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This file declares build flags for the SSL library configuration.
-#
-# TODO(brettw) this should probably be moved to src/crypto or somewhere, and
-# the global build dependency on it should be removed.
-#
-# PLEASE TRY TO AVOID ADDING FLAGS TO THIS FILE in cases where grit isn't
-# required. See the declare_args block of BUILDCONFIG.gn for advice on how
-# to set up feature flags.
-
-declare_args() {
-  # Use OpenSSL instead of NSS. This is used for all platforms but iOS. (See
-  # http://crbug.com/338886).
-  use_openssl = !is_ios
-}
-
-# True when we're using OpenSSL for representing certificates. When targeting
-# Android, the platform certificate library is used for certificate
-# verification. On other targets, this flag also enables OpenSSL for certificate
-# verification, but this configuration is unsupported.
-use_openssl_certs = is_android
-
-# True if NSS is used for certificate verification. Note that this is
-# independent from use_openssl. It is possible to use OpenSSL for the crypto
-# library, but NSS for the platform certificate library.
-use_nss_certs = false
diff --git a/build/config/features.gni b/build/config/features.gni
deleted file mode 100644
index 93b19dd1431..00000000000
--- a/build/config/features.gni
+++ /dev/null
@@ -1,204 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This file contains Chrome-feature-related build flags (see ui.gni for
-# UI-related ones). These should theoretically be moved to the build files of
-# the features themselves.
-#
-# However, today we have many "bad" dependencies on some of these flags from,
-# e.g. base, so they need to be global to match the GYP configuration. Also,
-# anything that needs a grit define must be in either this file or ui.gni.
-#
-# PLEASE TRY TO AVOID ADDING FLAGS TO THIS FILE in cases where grit isn't
-# required. See the declare_args block of BUILDCONFIG.gn for advice on how
-# to set up feature flags.
-
-import("//build/config/chrome_build.gni")
-if (is_android) {
-  import("//build/config/android/config.gni")
-}
-
-declare_args() {
-  # Multicast DNS.
-  enable_mdns = is_win || is_linux
-
-  enable_plugins = !is_android && !is_ios
-
-  # Enables Native Client support.
-  # TODO(GYP): Get NaCl linking on other platforms.
-  # Also, see if we can always get rid of enable_nacl_untrusted and
-  # enable_pnacl and always build them if enable_nacl is true.
-  # The "is_nacl" part of the condition is needed to ensure that
-  # the untrusted code is built properly; arguably it should be
-  # guarded by "is_nacl" directly rather than enable_nacl_untrusted, but
-  # this will go away when Mac and Win are working and we can just use
-  # the commented out logic.
-  # Eventually we want this to be:
-  #   enable_nacl = !is_ios && !is_android
-  enable_nacl = (is_linux && !is_chromeos && current_cpu == "x64") || is_nacl
-  enable_nacl_untrusted = enable_nacl
-  enable_pnacl = enable_nacl_untrusted
-
-  # If debug_devtools is set to true, JavaScript files for DevTools are stored
-  # as is and loaded from disk. Otherwise, a concatenated file is stored in
-  # resources.pak. It is still possible to load JS files from disk by passing
-  # --debug-devtools cmdline switch.
-  debug_devtools = false
-
-  # Enables WebRTC.
-  # TODO(GYP) make mac and android work.
-  enable_webrtc = !is_ios && !is_mac && !is_android
-
-  # Enables the Media Router.
-  enable_media_router = !is_ios && !is_android
-
-  # Enables proprietary codecs and demuxers; e.g. H264, MOV, AAC, and MP3.
-  # Android OS includes support for proprietary codecs regardless of building
-  # Chromium or Google Chrome. We also ship Google Chrome and Chromecast with
-  # proprietary codecs.
-  # TODO(GYP) The GYP build has || chromecast==1 for this:
-  proprietary_codecs = is_android || is_chrome_branded
-
-  enable_configuration_policy = true
-
-  # Enables support for background apps.
-  enable_background = !is_ios && !is_android
-
-  enable_captive_portal_detection = !is_android && !is_ios
-
-  # Enables use of the session service, which is enabled by default.
-  # Android stores them separately on the Java side.
-  enable_session_service = !is_android && !is_ios
-
-  enable_plugin_installation = is_win || is_mac
-
-  enable_app_list = !is_ios && !is_android
-
-  enable_supervised_users = !is_ios
-
-  enable_autofill_dialog = !is_ios
-
-  enable_google_now = !is_ios && !is_android
-
-  enable_one_click_signin = is_win || is_mac || (is_linux && !is_chromeos)
-
-  enable_remoting = !is_ios && !is_android
-
-  # Enable hole punching for the protected video.
-  enable_video_hole = is_android
-
-  # Enables browser side Content Decryption Modules. Required for embedders
-  # (e.g. Android and ChromeCast) that use a browser side CDM.
-  enable_browser_cdms = is_android
-
-  # Variable safe_browsing is used to control the build time configuration
-  # for safe browsing feature. Safe browsing can be compiled in 4 different
-  # levels: 0 disables it, 1 enables it fully, and 2 enables only UI and
-  # reporting features for use with Data Saver on Mobile, and 3 enables
-  # extended mobile protection via an external API.  When 3 is fully deployed,
-  # it will replace 2.
-  if (is_android) {
-    safe_browsing_mode = 2
-  } else if (is_ios) {
-    safe_browsing_mode = 0
-  } else {
-    safe_browsing_mode = 1
-  }
-}
-
-# Additional dependent variables -----------------------------------------------
-
-# Set the version of CLD.
-#   0: Don't specify the version. This option is for the Finch testing.
-#   1: Use only CLD1.
-#   2: Use only CLD2.
-if (is_android) {
-  cld_version = 1
-} else {
-  cld_version = 2
-}
-
-# libudev usage. This currently only affects the content layer.
-use_udev = is_linux
-
-# Enable the spell checker.
-enable_spellcheck = !is_android
-
-# Use the operating system's spellchecker rather than hunspell.
-use_platform_spellchecker = is_android || is_mac
-
-enable_pepper_cdms = enable_plugins && (is_linux || is_mac || is_win)
-
-# Enable basic printing support and UI.
-enable_basic_printing = !is_chromeos
-
-# Enable printing with print preview. It does not imply
-# enable_basic_printing. It's possible to build Chrome with preview only.
-enable_print_preview = !is_android
-
-# The seccomp-bpf sandbox is only supported on three architectures
-# currently.
-# Do not disable seccomp_bpf anywhere without talking to
-# security@chromium.org!
-use_seccomp_bpf = (is_linux || is_android) &&
-                  (current_cpu == "x86" || current_cpu == "x64" ||
-                   current_cpu == "arm" || current_cpu == "mipsel")
-
-# Enable notifications everywhere except iOS.
-enable_notifications = !is_ios
-
-# TODO(brettw) this should be moved to net and only dependents get this define.
-disable_ftp_support = is_ios
-
-enable_web_speech = !is_android && !is_ios
-
-use_dbus = is_linux
-
-enable_extensions = !is_android && !is_ios
-
-enable_task_manager = !is_ios && !is_android
-
-use_cups = is_desktop_linux || is_mac
-
-enable_themes = !is_android && !is_ios
-
-# TODO(scottmg) remove this when we've fixed printing.
-win_pdf_metafile_for_printing = true
-
-# Whether we are using the rlz library or not.  Platforms like Android send
-# rlz codes for searches but do not use the library.
-enable_rlz_support = is_win || is_mac || is_ios || is_chromeos
-enable_rlz = is_chrome_branded && enable_rlz_support
-
-enable_settings_app = enable_app_list && !is_chromeos
-
-enable_service_discovery = enable_mdns || is_mac
-
-enable_wifi_bootstrapping = is_win || is_mac
-
-# Image loader extension is enabled on ChromeOS only.
-enable_image_loader_extension = is_chromeos
-
-# Chrome OS: whether to also build the upcoming version of
-# ChromeVox, which can then be enabled via a command-line switch.
-enable_chromevox_next = false
-
-# Use brlapi from brltty for braille display support.
-use_brlapi = is_chromeos
-
-# Option controlling the use of GConf (the classic GNOME configuration
-# system).
-# TODO(GYP) also require !embedded to enable.
-use_gconf = is_linux && !is_chromeos
-
-# Hangout services is an extension that adds extra features to Hangouts.
-# For official GYP builds, this flag is set, it will likely need to be
-# parameterized in the future for a similar use.
-enable_hangout_services_extension = false
-
-# Whether to back up data before sync.
-enable_pre_sync_backup = is_win || is_mac || (is_linux && !is_chromeos)
-
-# WebVR support disabled until platform implementations have been added
-enable_webvr = false
diff --git a/build/config/linux/BUILD.gn b/build/config/linux/BUILD.gn
index 71a73b2d625..4b02a258deb 100644
--- a/build/config/linux/BUILD.gn
+++ b/build/config/linux/BUILD.gn
@@ -2,10 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/linux/pkg_config.gni")
-import("//build/config/features.gni")
 import("//build/config/sysroot.gni")
-import("//build/config/ui.gni")
 
 config("sdk") {
   if (sysroot != "") {
@@ -22,41 +19,3 @@ config("sdk") {
                              "value") ]
   }
 }
-
-config("fontconfig") {
-  libs = [ "fontconfig" ]
-}
-
-pkg_config("freetype2") {
-  packages = [ "freetype2" ]
-}
-
-config("x11") {
-  libs = [
-    "X11",
-    "Xcomposite",
-    "Xcursor",
-    "Xdamage",
-    "Xext",
-    "Xfixes",
-    "Xi",
-    "Xrender",
-    "Xtst",
-  ]
-}
-
-config("xrandr") {
-  libs = [ "Xrandr" ]
-}
-
-config("xinerama") {
-  libs = [ "Xinerama" ]
-}
-
-config("xcomposite") {
-  libs = [ "Xcomposite" ]
-}
-
-config("xext") {
-  libs = [ "Xext" ]
-}
diff --git a/build/config/sysroot.gni b/build/config/sysroot.gni
index 5bce02e2985..37faae059c3 100644
--- a/build/config/sysroot.gni
+++ b/build/config/sysroot.gni
@@ -5,8 +5,6 @@
 # This header file defines the "sysroot" variable which is the absolute path
 # of the sysroot. If no sysroot applies, the variable will be an empty string.
 
-import("//build/config/chrome_build.gni")
-
 declare_args() {
   # The absolute path of the sysroot that is applied when compiling using
   # the target toolchain.
@@ -32,29 +30,9 @@ if (current_toolchain == default_toolchain && target_sysroot != "") {
   } else {
     sysroot = ""
   }
-} else if (is_linux && is_chrome_branded && is_official_build && !is_chromeos) {
-  # For official builds, use the sysroot checked into the internal source repo
-  # so that the builds work on older versions of Linux.
-  if (current_cpu == "x64") {
-    sysroot = rebase_path("//build/linux/debian_wheezy_amd64-sysroot")
-  } else if (current_cpu == "x86") {
-    sysroot = rebase_path("//build/linux/debian_wheezy_i386-sysroot")
-  } else {
-    # Any other builds don't use a sysroot.
-    sysroot = ""
-  }
-} else if (is_linux && !is_chromeos) {
-  if (current_cpu == "mipsel") {
-    sysroot = rebase_path("//mipsel-sysroot/sysroot")
-  } else {
-    sysroot = ""
-  }
 } else if (is_mac) {
   import("//build/config/mac/mac_sdk.gni")
   sysroot = mac_sdk_path
-} else if (is_ios) {
-  import("//build/config/ios/ios_sdk.gni")
-  sysroot = ios_sdk_path
 } else {
   sysroot = ""
 }
diff --git a/build/config/ui.gni b/build/config/ui.gni
deleted file mode 100644
index c2dff4a87df..00000000000
--- a/build/config/ui.gni
+++ /dev/null
@@ -1,68 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This file contains UI-related build flags. It should theoretically be in the
-# src/ui directory and only things that depend on the ui module should get the
-# definitions.
-#
-# However, today we have many "bad" dependencies on some of these flags from,
-# e.g. base, so they need to be global.
-#
-# See also build/config/features.gni
-
-declare_args() {
-  # Indicates if Ash is enabled. Ash is the Aura Shell which provides a
-  # desktop-like environment for Aura. Requires use_aura = true
-  use_ash = is_win || is_linux
-
-  # Indicates if Ozone is enabled. Ozone is a low-level library layer for Linux
-  # that does not require X11.
-  use_ozone = false
-
-  # Indicates if GLFW is enabled. GLFW is an abstraction layer for the
-  # windowing system and OpenGL rendering, providing cross-platform support
-  # for creating windows and OpenGL surfaces and contexts, and handling
-  # window system events and input.
-  use_glfw = false
-
-  # Support ChromeOS touchpad gestures with ozone.
-  use_evdev_gestures = false
-
-  # Indicates if Aura is enabled. Aura is a low-level windowing library, sort
-  # of a replacement for GDI or GTK.
-  use_aura = is_win || is_linux
-
-  # True means the UI is built using the "views" framework.
-  toolkit_views = is_mac || is_win || is_chromeos || use_aura
-
-  # Whether the entire browser uses toolkit-views on Mac instead of Cocoa.
-  mac_views_browser = false
-
-  # Whether we should use glib, a low level C utility library.
-  use_glib = is_linux && !use_ozone
-}
-
-# Additional dependent variables -----------------------------------------------
-#
-# These variables depend on other variables and can't be set externally.
-
-use_cairo = false
-use_pango = false
-
-# Use GPU accelerated cross process image transport by default on linux builds
-# with the Aura window manager.
-ui_compositor_image_transport = use_aura && is_linux
-
-use_default_render_theme = use_aura || is_linux
-
-# Indicates if the UI toolkit depends on X11.
-use_x11 = is_linux && !use_ozone && !use_glfw
-
-use_ozone_evdev = use_ozone
-
-use_clipboard_aurax11 = is_linux && use_aura && use_x11
-
-enable_hidpi = is_mac || is_chromeos || is_win || is_linux
-
-enable_topchrome_md = false
diff --git a/build/config/win/BUILD.gn b/build/config/win/BUILD.gn
index 261a1ac4def..c9391005a93 100644
--- a/build/config/win/BUILD.gn
+++ b/build/config/win/BUILD.gn
@@ -141,7 +141,7 @@ config("no_incremental_linking") {
 # config should be applied to large modules to turn off incremental linking
 # when it won't work.
 config("default_large_module_incremental_linking") {
-  if (symbol_level > 0 && (current_cpu == "x86" || !is_component_build)) {
+  if (current_cpu == "x86" || !is_component_build) {
     # When symbols are on, things get so large that the tools fail due to the
     # size of the .ilk files.
     ldflags = incremental_linking_off_switch
diff --git a/build/gyp_chromium b/build/gyp_chromium
deleted file mode 100755
index 9dac8710ff2..00000000000
--- a/build/gyp_chromium
+++ /dev/null
@@ -1,333 +0,0 @@
-#!/usr/bin/env python
-
-# Copyright (c) 2012 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This script is wrapper for Chromium that adds some support for how GYP
-# is invoked by Chromium beyond what can be done in the gclient hooks.
-
-import argparse
-import glob
-import gyp_environment
-import os
-import re
-import shlex
-import subprocess
-import string
-import sys
-import vs_toolchain
-
-script_dir = os.path.dirname(os.path.realpath(__file__))
-chrome_src = os.path.abspath(os.path.join(script_dir, os.pardir))
-
-sys.path.insert(0, os.path.join(chrome_src, 'tools', 'gyp', 'pylib'))
-import gyp
-
-# Assume this file is in a one-level-deep subdirectory of the source root.
-SRC_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
-
-# Add paths so that pymod_do_main(...) can import files.
-sys.path.insert(1, os.path.join(chrome_src, 'android_webview', 'tools'))
-sys.path.insert(1, os.path.join(chrome_src, 'build', 'android', 'gyp'))
-sys.path.insert(1, os.path.join(chrome_src, 'chrome', 'tools', 'build'))
-sys.path.insert(1, os.path.join(chrome_src, 'chromecast', 'tools', 'build'))
-sys.path.insert(1, os.path.join(chrome_src, 'ios', 'chrome', 'tools', 'build'))
-sys.path.insert(1, os.path.join(chrome_src, 'native_client', 'build'))
-sys.path.insert(1, os.path.join(chrome_src, 'native_client_sdk', 'src',
-    'build_tools'))
-sys.path.insert(1, os.path.join(chrome_src, 'remoting', 'tools', 'build'))
-sys.path.insert(1, os.path.join(chrome_src, 'third_party', 'liblouis'))
-sys.path.insert(1, os.path.join(chrome_src, 'third_party', 'WebKit',
-    'Source', 'build', 'scripts'))
-sys.path.insert(1, os.path.join(chrome_src, 'tools'))
-sys.path.insert(1, os.path.join(chrome_src, 'tools', 'generate_shim_headers'))
-sys.path.insert(1, os.path.join(chrome_src, 'tools', 'grit'))
-
-# On Windows, Psyco shortens warm runs of build/gyp_chromium by about
-# 20 seconds on a z600 machine with 12 GB of RAM, from 90 down to 70
-# seconds.  Conversely, memory usage of build/gyp_chromium with Psyco
-# maxes out at about 158 MB vs. 132 MB without it.
-#
-# Psyco uses native libraries, so we need to load a different
-# installation depending on which OS we are running under. It has not
-# been tested whether using Psyco on our Mac and Linux builds is worth
-# it (the GYP running time is a lot shorter, so the JIT startup cost
-# may not be worth it).
-if sys.platform == 'win32':
-  try:
-    sys.path.insert(0, os.path.join(chrome_src, 'third_party', 'psyco_win32'))
-    import psyco
-  except:
-    psyco = None
-else:
-  psyco = None
-
-
-def GetSupplementalFiles():
-  """Returns a list of the supplemental files that are included in all GYP
-  sources."""
-  return glob.glob(os.path.join(chrome_src, '*', 'supplement.gypi'))
-
-
-def ProcessGypDefinesItems(items):
-  """Converts a list of strings to a list of key-value pairs."""
-  result = []
-  for item in items:
-    tokens = item.split('=', 1)
-    # Some GYP variables have hyphens, which we don't support.
-    if len(tokens) == 2:
-      result += [(tokens[0], tokens[1])]
-    else:
-      # No value supplied, treat it as a boolean and set it. Note that we
-      # use the string '1' here so we have a consistent definition whether
-      # you do 'foo=1' or 'foo'.
-      result += [(tokens[0], '1')]
-  return result
-
-
-def GetGypVars(supplemental_files):
-  """Returns a dictionary of all GYP vars."""
-  # Find the .gyp directory in the user's home directory.
-  home_dot_gyp = os.environ.get('GYP_CONFIG_DIR', None)
-  if home_dot_gyp:
-    home_dot_gyp = os.path.expanduser(home_dot_gyp)
-  if not home_dot_gyp:
-    home_vars = ['HOME']
-    if sys.platform in ('cygwin', 'win32'):
-      home_vars.append('USERPROFILE')
-    for home_var in home_vars:
-      home = os.getenv(home_var)
-      if home != None:
-        home_dot_gyp = os.path.join(home, '.gyp')
-        if not os.path.exists(home_dot_gyp):
-          home_dot_gyp = None
-        else:
-          break
-
-  if home_dot_gyp:
-    include_gypi = os.path.join(home_dot_gyp, "include.gypi")
-    if os.path.exists(include_gypi):
-      supplemental_files += [include_gypi]
-
-  # GYP defines from the supplemental.gypi files.
-  supp_items = []
-  for supplement in supplemental_files:
-    with open(supplement, 'r') as f:
-      try:
-        file_data = eval(f.read(), {'__builtins__': None}, None)
-      except SyntaxError, e:
-        e.filename = os.path.abspath(supplement)
-        raise
-      variables = file_data.get('variables', [])
-      for v in variables:
-        supp_items += [(v, str(variables[v]))]
-
-  # GYP defines from the environment.
-  env_items = ProcessGypDefinesItems(
-      shlex.split(os.environ.get('GYP_DEFINES', '')))
-
-  # GYP defines from the command line.
-  parser = argparse.ArgumentParser()
-  parser.add_argument('-D', dest='defines', action='append', default=[])
-  cmdline_input_items = parser.parse_known_args()[0].defines
-  cmdline_items = ProcessGypDefinesItems(cmdline_input_items)
-
-  vars_dict = dict(supp_items + env_items + cmdline_items)
-  return vars_dict
-
-
-def GetOutputDirectory():
-  """Returns the output directory that GYP will use."""
-
-  # Handle command line generator flags.
-  parser = argparse.ArgumentParser()
-  parser.add_argument('-G', dest='genflags', default=[], action='append')
-  genflags = parser.parse_known_args()[0].genflags
-
-  # Handle generator flags from the environment.
-  genflags += shlex.split(os.environ.get('GYP_GENERATOR_FLAGS', ''))
-
-  needle = 'output_dir='
-  for item in genflags:
-    if item.startswith(needle):
-      return item[len(needle):]
-
-  return 'out'
-
-
-def additional_include_files(supplemental_files, args=[]):
-  """
-  Returns a list of additional (.gypi) files to include, without duplicating
-  ones that are already specified on the command line. The list of supplemental
-  include files is passed in as an argument.
-  """
-  # Determine the include files specified on the command line.
-  # This doesn't cover all the different option formats you can use,
-  # but it's mainly intended to avoid duplicating flags on the automatic
-  # makefile regeneration which only uses this format.
-  specified_includes = set()
-  for arg in args:
-    if arg.startswith('-I') and len(arg) > 2:
-      specified_includes.add(os.path.realpath(arg[2:]))
-
-  result = []
-  def AddInclude(path):
-    if os.path.realpath(path) not in specified_includes:
-      result.append(path)
-
-  if os.environ.get('GYP_INCLUDE_FIRST') != None:
-    AddInclude(os.path.join(chrome_src, os.environ.get('GYP_INCLUDE_FIRST')))
-
-  # Always include common.gypi.
-  AddInclude(os.path.join(script_dir, 'common.gypi'))
-
-  # Optionally add supplemental .gypi files if present.
-  for supplement in supplemental_files:
-    AddInclude(supplement)
-
-  if os.environ.get('GYP_INCLUDE_LAST') != None:
-    AddInclude(os.path.join(chrome_src, os.environ.get('GYP_INCLUDE_LAST')))
-
-  return result
-
-
-if __name__ == '__main__':
-  # Disabling garbage collection saves about 1 second out of 16 on a Linux
-  # z620 workstation. Since this is a short-lived process it's not a problem to
-  # leak a few cyclyc references in order to spare the CPU cycles for
-  # scanning the heap.
-  import gc
-  gc.disable()
-
-  args = sys.argv[1:]
-
-  use_analyzer = len(args) and args[0] == '--analyzer'
-  if use_analyzer:
-    args.pop(0)
-    os.environ['GYP_GENERATORS'] = 'analyzer'
-    args.append('-Gconfig_path=' + args.pop(0))
-    args.append('-Ganalyzer_output_path=' + args.pop(0))
-
-  if int(os.environ.get('GYP_CHROMIUM_NO_ACTION', 0)):
-    print 'Skipping gyp_chromium due to GYP_CHROMIUM_NO_ACTION env var.'
-    sys.exit(0)
-
-  # Use the Psyco JIT if available.
-  if psyco:
-    psyco.profile()
-    print "Enabled Psyco JIT."
-
-  # Fall back on hermetic python if we happen to get run under cygwin.
-  # TODO(bradnelson): take this out once this issue is fixed:
-  #    http://code.google.com/p/gyp/issues/detail?id=177
-  if sys.platform == 'cygwin':
-    import find_depot_tools
-    depot_tools_path = find_depot_tools.add_depot_tools_to_path()
-    python_dir = sorted(glob.glob(os.path.join(depot_tools_path,
-                                               'python2*_bin')))[-1]
-    env = os.environ.copy()
-    env['PATH'] = python_dir + os.pathsep + env.get('PATH', '')
-    cmd = [os.path.join(python_dir, 'python.exe')] + sys.argv
-    sys.exit(subprocess.call(cmd, env=env))
-
-  # This could give false positives since it doesn't actually do real option
-  # parsing.  Oh well.
-  gyp_file_specified = any(arg.endswith('.gyp') for arg in args)
-
-  gyp_environment.SetEnvironment()
-
-  # If we didn't get a file, check an env var, and then fall back to
-  # assuming 'all.gyp' from the same directory as the script.
-  if not gyp_file_specified:
-    gyp_file = os.environ.get('CHROMIUM_GYP_FILE')
-    if gyp_file:
-      # Note that CHROMIUM_GYP_FILE values can't have backslashes as
-      # path separators even on Windows due to the use of shlex.split().
-      args.extend(shlex.split(gyp_file))
-    else:
-      args.append(os.path.join(script_dir, 'all.gyp'))
-
-  supplemental_includes = GetSupplementalFiles()
-  gyp_vars_dict = GetGypVars(supplemental_includes)
-  # There shouldn't be a circular dependency relationship between .gyp files,
-  # but in Chromium's .gyp files, on non-Mac platforms, circular relationships
-  # currently exist.  The check for circular dependencies is currently
-  # bypassed on other platforms, but is left enabled on iOS, where a violation
-  # of the rule causes Xcode to misbehave badly.
-  # TODO(mark): Find and kill remaining circular dependencies, and remove this
-  # option.  http://crbug.com/35878.
-  # TODO(tc): Fix circular dependencies in ChromiumOS then add linux2 to the
-  # list.
-  if gyp_vars_dict.get('OS') != 'ios':
-    args.append('--no-circular-check')
-
-  # libtool on Mac warns about duplicate basenames in static libraries, so
-  # they're disallowed in general by gyp. We are lax on this point, so disable
-  # this check other than on Mac. GN does not use static libraries as heavily,
-  # so over time this restriction will mostly go away anyway, even on Mac.
-  # https://code.google.com/p/gyp/issues/detail?id=384
-  if sys.platform != 'darwin':
-    args.append('--no-duplicate-basename-check')
-
-  # We explicitly don't support the make gyp generator (crbug.com/348686). Be
-  # nice and fail here, rather than choking in gyp.
-  if re.search(r'(^|,|\s)make($|,|\s)', os.environ.get('GYP_GENERATORS', '')):
-    print 'Error: make gyp generator not supported (check GYP_GENERATORS).'
-    sys.exit(1)
-
-  # We explicitly don't support the native msvs gyp generator. Be nice and
-  # fail here, rather than generating broken projects.
-  if re.search(r'(^|,|\s)msvs($|,|\s)', os.environ.get('GYP_GENERATORS', '')):
-    print 'Error: msvs gyp generator not supported (check GYP_GENERATORS).'
-    print 'Did you mean to use the `msvs-ninja` generator?'
-    sys.exit(1)
-
-  # If CHROMIUM_GYP_SYNTAX_CHECK is set to 1, it will invoke gyp with --check
-  # to enfore syntax checking.
-  syntax_check = os.environ.get('CHROMIUM_GYP_SYNTAX_CHECK')
-  if syntax_check and int(syntax_check):
-    args.append('--check')
-
-  # TODO(dmikurube): Remove these checks and messages after a while.
-  if ('linux_use_tcmalloc' in gyp_vars_dict or
-      'android_use_tcmalloc' in gyp_vars_dict):
-    print '*****************************************************************'
-    print '"linux_use_tcmalloc" and "android_use_tcmalloc" are deprecated!'
-    print '-----------------------------------------------------------------'
-    print 'You specify "linux_use_tcmalloc" or "android_use_tcmalloc" in'
-    print 'your GYP_DEFINES. Please switch them into "use_allocator" now.'
-    print 'See http://crbug.com/345554 for the details.'
-    print '*****************************************************************'
-
-  # Automatically turn on crosscompile support for platforms that need it.
-  # (The Chrome OS build sets CC_host / CC_target which implicitly enables
-  # this mode.)
-  if all(('ninja' in os.environ.get('GYP_GENERATORS', ''),
-          gyp_vars_dict.get('OS') in ['android', 'ios'],
-          'GYP_CROSSCOMPILE' not in os.environ)):
-    os.environ['GYP_CROSSCOMPILE'] = '1'
-  if gyp_vars_dict.get('OS') == 'android':
-    args.append('--check')
-
-  args.extend(
-      ['-I' + i for i in additional_include_files(supplemental_includes, args)])
-
-  args.extend(['-D', 'gyp_output_dir=' + GetOutputDirectory()])
-
-  if not use_analyzer:
-    print 'Updating projects from gyp files...'
-    sys.stdout.flush()
-
-  # Off we go...
-  gyp_rc = gyp.main(args)
-
-  if not use_analyzer:
-    vs2013_runtime_dll_dirs = vs_toolchain.SetEnvironmentAndGetRuntimeDllDirs()
-    if vs2013_runtime_dll_dirs:
-      x64_runtime, x86_runtime = vs2013_runtime_dll_dirs
-      vs_toolchain.CopyVsRuntimeDlls(
-        os.path.join(chrome_src, GetOutputDirectory()),
-        (x86_runtime, x64_runtime))
-
-  sys.exit(gyp_rc)
diff --git a/build/gyp_chromium.py b/build/gyp_chromium.py
deleted file mode 100644
index f9e8ac8ed83..00000000000
--- a/build/gyp_chromium.py
+++ /dev/null
@@ -1,18 +0,0 @@
-# Copyright 2012 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This file is (possibly, depending on python version) imported by
-# gyp_chromium when GYP_PARALLEL=1 and it creates sub-processes
-# through the multiprocessing library.
-
-# Importing in Python 2.6 (fixed in 2.7) on Windows doesn't search for
-# imports that don't end in .py (and aren't directories with an
-# __init__.py). This wrapper makes "import gyp_chromium" work with
-# those old versions and makes it possible to execute gyp_chromium.py
-# directly on Windows where the extension is useful.
-
-import os
-
-path = os.path.abspath(os.path.split(__file__)[0])
-execfile(os.path.join(path, 'gyp_chromium'))
diff --git a/build/gyp_chromium_test.py b/build/gyp_chromium_test.py
deleted file mode 100755
index 0c0e479d1c3..00000000000
--- a/build/gyp_chromium_test.py
+++ /dev/null
@@ -1,66 +0,0 @@
-#!/usr/bin/env python
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import os
-import sys
-import unittest
-
-SCRIPT_DIR = os.path.abspath(os.path.dirname(__file__))
-SRC_DIR = os.path.dirname(SCRIPT_DIR)
-
-sys.path.append(os.path.join(SRC_DIR, 'third_party', 'pymock'))
-
-import mock
-
-# TODO(sbc): Make gyp_chromium more testable by putting the code in
-# a .py file.
-gyp_chromium = __import__('gyp_chromium')
-
-
-class TestGetOutputDirectory(unittest.TestCase):
-  @mock.patch('os.environ', {})
-  @mock.patch('sys.argv', [__file__])
-  def testDefaultValue(self):
-    self.assertEqual(gyp_chromium.GetOutputDirectory(), 'out')
-
-  @mock.patch('os.environ', {'GYP_GENERATOR_FLAGS': 'output_dir=envfoo'})
-  @mock.patch('sys.argv', [__file__])
-  def testEnvironment(self):
-    self.assertEqual(gyp_chromium.GetOutputDirectory(), 'envfoo')
-
-  @mock.patch('os.environ', {'GYP_GENERATOR_FLAGS': 'output_dir=envfoo'})
-  @mock.patch('sys.argv', [__file__, '-Goutput_dir=cmdfoo'])
-  def testGFlagOverridesEnv(self):
-    self.assertEqual(gyp_chromium.GetOutputDirectory(), 'cmdfoo')
-
-  @mock.patch('os.environ', {})
-  @mock.patch('sys.argv', [__file__, '-G', 'output_dir=foo'])
-  def testGFlagWithSpace(self):
-    self.assertEqual(gyp_chromium.GetOutputDirectory(), 'foo')
-
-
-class TestGetGypVars(unittest.TestCase):
-  @mock.patch('os.environ', {})
-  def testDefault(self):
-    self.assertEqual(gyp_chromium.GetGypVars([]), {})
-
-  @mock.patch('os.environ', {})
-  @mock.patch('sys.argv', [__file__, '-D', 'foo=bar'])
-  def testDFlags(self):
-    self.assertEqual(gyp_chromium.GetGypVars([]), {'foo': 'bar'})
-
-  @mock.patch('os.environ', {})
-  @mock.patch('sys.argv', [__file__, '-D', 'foo'])
-  def testDFlagsNoValue(self):
-    self.assertEqual(gyp_chromium.GetGypVars([]), {'foo': '1'})
-
-  @mock.patch('os.environ', {})
-  @mock.patch('sys.argv', [__file__, '-D', 'foo=bar', '-Dbaz'])
-  def testDFlagMulti(self):
-    self.assertEqual(gyp_chromium.GetGypVars([]), {'foo': 'bar', 'baz': '1'})
-
-
-if __name__ == '__main__':
-  unittest.main()
diff --git a/build/json_schema_api.gni b/build/json_schema_api.gni
deleted file mode 100644
index e1c2d33409d..00000000000
--- a/build/json_schema_api.gni
+++ /dev/null
@@ -1,242 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Defines a static library corresponding to the output of schema compiler tools
-# over a set of extensions API schemas (IDL or JSON format.) The library target
-# has implicit hard dependencies on all schema files listed by the invoker and
-# is itself a hard dependency.
-#
-# Invocations of this template may use the following variables:
-#
-# sources [required] A list of schema files to be compiled.
-#
-# root_namespace [required]
-#     A Python string substituion pattern used to generate the C++
-#     namespace for each API. Use %(namespace)s to replace with the API
-#     namespace, like "toplevel::%(namespace)s_api".
-#
-# schema_include_rules [optional]
-#     A list of paths to include when searching for referenced objects,
-#     with the namespace separated by a :.
-#     Example:
-#       [ '/foo/bar:Foo::Bar::%(namespace)s' ]
-#
-# schemas [optional, default = false]
-#   Boolean indicating if the schema files should be generated.
-#
-# bundle [optional, default = false]
-#   Boolean indicating if the schema bundle files should be generated.
-#
-# bundle_registration [optional, default = false]
-#   Boolean indicating if the API registration bundle files should be generated.
-#
-# impl_dir [required if bundle_registration = true, otherwise unused]
-#   The path containing C++ implementations of API functions. This path is
-#   used as the root path when looking for {schema}/{schema}_api.h headers
-#   when generating API registration bundles. Such headers, if found, are
-#   automatically included by the generated code.
-#
-# uncompiled_sources [optional, only used when bundle = true or
-#     bundle_registration = true]
-#   A list of schema files which should not be compiled, but which should still
-#   be processed for API bundle generation.
-#
-# deps [optional]
-#   If any deps are specified they will be inherited by the static library
-#   target.
-#
-# generate_static_library [optional, defaults to false]
-#   Produces a static library instead of a source_set.
-#
-# The generated library target also inherits the visibility and output_name
-# of its invoker.
-
-template("json_schema_api") {
-  assert(defined(invoker.sources),
-         "\"sources\" must be defined for the $target_name template.")
-  assert(defined(invoker.root_namespace),
-         "\"root_namespace\" must be defined for the $target_name template.")
-
-  schemas = defined(invoker.schemas) && invoker.schemas
-  bundle = defined(invoker.bundle) && invoker.bundle
-  bundle_registration =
-      defined(invoker.bundle_registration) && invoker.bundle_registration
-
-  schema_include_rules = ""
-  if (defined(invoker.schema_include_rules)) {
-    schema_include_rules = invoker.schema_include_rules
-  }
-
-  # Keep a copy of the target_name here since it will be trampled
-  # in nested targets.
-  target_visibility = [ ":$target_name" ]
-
-  generated_config_name = target_name + "_generated_config"
-  config(generated_config_name) {
-    include_dirs = [ root_gen_dir ]
-    visibility = target_visibility
-  }
-
-  root_namespace = invoker.root_namespace
-
-  compiler_root = "//tools/json_schema_compiler"
-  compiler_script = "$compiler_root/compiler.py"
-  compiler_sources = [
-    "$compiler_root/cc_generator.py",
-    "$compiler_root/code.py",
-    "$compiler_root/compiler.py",
-    "$compiler_root/cpp_generator.py",
-    "$compiler_root/cpp_type_generator.py",
-    "$compiler_root/cpp_util.py",
-    "$compiler_root/h_generator.py",
-    "$compiler_root/idl_schema.py",
-    "$compiler_root/model.py",
-    "$compiler_root/util_cc_helper.py",
-  ]
-
-  if (schemas) {
-    schema_generator_name = target_name + "_schema_generator"
-    action_foreach(schema_generator_name) {
-      script = compiler_script
-      sources = invoker.sources
-      inputs = compiler_sources
-      outputs = [
-        "$target_gen_dir/{{source_name_part}}.cc",
-        "$target_gen_dir/{{source_name_part}}.h",
-      ]
-      args = [
-        "{{source}}",
-        "--root=" + rebase_path("//", root_build_dir),
-        "--destdir=" + rebase_path(root_gen_dir, root_build_dir),
-        "--namespace=$root_namespace",
-        "--generator=cpp",
-        "--include-rules=$schema_include_rules",
-      ]
-
-      if (defined(invoker.visibility)) {
-        # If visibility is restricted, add our own target to it.
-        visibility = invoker.visibility + target_visibility
-      }
-    }
-  }
-
-  if (bundle) {
-    uncompiled_sources = []
-    if (defined(invoker.uncompiled_sources)) {
-      uncompiled_sources = invoker.uncompiled_sources
-    }
-
-    bundle_generator_schema_name = target_name + "_bundle_generator_schema"
-    action(bundle_generator_schema_name) {
-      script = compiler_script
-      inputs = compiler_sources + invoker.sources + uncompiled_sources
-      outputs = [
-        "$target_gen_dir/generated_schemas.cc",
-        "$target_gen_dir/generated_schemas.h",
-      ]
-      args = [
-               "--root=" + rebase_path("//", root_build_dir),
-               "--destdir=" + rebase_path(root_gen_dir, root_build_dir),
-               "--namespace=$root_namespace",
-               "--generator=cpp-bundle-schema",
-               "--include-rules=$schema_include_rules",
-             ] + rebase_path(invoker.sources, root_build_dir) +
-             rebase_path(uncompiled_sources, root_build_dir)
-    }
-  }
-
-  if (bundle_registration) {
-    uncompiled_sources = []
-    if (defined(invoker.uncompiled_sources)) {
-      uncompiled_sources = invoker.uncompiled_sources
-    }
-
-    assert(defined(invoker.impl_dir),
-           "\"impl_dir\" must be defined for the $target_name template.")
-
-    # Child directory inside the generated file tree.
-    gen_child_dir = rebase_path(invoker.impl_dir, "//")
-
-    bundle_generator_registration_name =
-        target_name + "_bundle_generator_registration"
-    action(bundle_generator_registration_name) {
-      script = compiler_script
-      inputs = compiler_sources + invoker.sources + uncompiled_sources
-      outputs = [
-        "$root_gen_dir/$gen_child_dir/generated_api_registration.cc",
-        "$root_gen_dir/$gen_child_dir/generated_api_registration.h",
-      ]
-      args = [
-               "--root=" + rebase_path("//", root_build_dir),
-               "--destdir=" + rebase_path(root_gen_dir, root_build_dir),
-               "--namespace=$root_namespace",
-               "--generator=cpp-bundle-registration",
-               "--impl-dir=$gen_child_dir",
-               "--include-rules=$schema_include_rules",
-             ] + rebase_path(invoker.sources, root_build_dir) +
-             rebase_path(uncompiled_sources, root_build_dir)
-    }
-  }
-
-  # Compute the contents of the library/source set.
-  lib_sources = invoker.sources
-  lib_deps = []
-  lib_public_deps = []
-  lib_extra_configs = []
-
-  if (schemas) {
-    lib_sources += get_target_outputs(":$schema_generator_name")
-    lib_public_deps += [ ":$schema_generator_name" ]
-    lib_deps += [ "//tools/json_schema_compiler:generated_api_util" ]
-    lib_extra_configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
-  }
-
-  if (bundle) {
-    lib_sources += get_target_outputs(":$bundle_generator_schema_name")
-    lib_deps += [ ":$bundle_generator_schema_name" ]
-  }
-
-  if (bundle_registration) {
-    lib_sources += get_target_outputs(":$bundle_generator_registration_name")
-    lib_deps += [ ":$bundle_generator_registration_name" ]
-  }
-
-  if (defined(invoker.deps)) {
-    lib_deps += invoker.deps
-  }
-
-  # Generate either a static library or a source set.
-  if (defined(invoker.generate_static_library) &&
-      invoker.generate_static_library) {
-    static_library(target_name) {
-      sources = lib_sources
-      deps = lib_deps
-      public_deps = lib_public_deps
-      configs += lib_extra_configs
-      public_configs = [ ":$generated_config_name" ]
-
-      if (defined(invoker.visibility)) {
-        visibility = invoker.visibility
-      }
-      if (defined(invoker.output_name)) {
-        output_name = invoker.output_name
-      }
-    }
-  } else {
-    source_set(target_name) {
-      sources = lib_sources
-      deps = lib_deps
-      public_deps = lib_public_deps
-      configs += lib_extra_configs
-      public_configs = [ ":$generated_config_name" ]
-
-      if (defined(invoker.visibility)) {
-        visibility = invoker.visibility
-      }
-      if (defined(invoker.output_name)) {
-        output_name = invoker.output_name
-      }
-    }
-  }
-}
diff --git a/build/json_schema_bundle_compile.gypi b/build/json_schema_bundle_compile.gypi
deleted file mode 100644
index a3020136d3f..00000000000
--- a/build/json_schema_bundle_compile.gypi
+++ /dev/null
@@ -1,83 +0,0 @@
-# Copyright (c) 2012 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-{
-  'variables': {
-    # When including this gypi, the following variables must be set:
-    #   schema_files:
-    #     An array of json or idl files that comprise the api model.
-    #   schema_include_rules (optional):
-    #     An array of paths to include when searching for referenced objects,
-    #     with the namespace separated by a :.
-    #     Example:
-    #       [ '/foo/bar:Foo::Bar::%(namespace)s' ]
-    #   cc_dir:
-    #     The directory to put the generated code in.
-    #   root_namespace:
-    #     A Python string substituion pattern used to generate the C++
-    #     namespace for each API. Use %(namespace)s to replace with the API
-    #     namespace, like "toplevel::%(namespace)s_api".
-    #
-    # Functions and namespaces can be excluded by setting "nocompile" to true.
-    # The default root path of API implementation sources is
-    # chrome/browser/extensions/api and can be overridden by setting "impl_dir".
-    'api_gen_dir': '<(DEPTH)/tools/json_schema_compiler',
-    'api_gen': '<(api_gen_dir)/compiler.py',
-    'generator_files': [
-      '<(api_gen_dir)/cc_generator.py',
-      '<(api_gen_dir)/code.py',
-      '<(api_gen_dir)/compiler.py',
-      '<(api_gen_dir)/cpp_bundle_generator.py',
-      '<(api_gen_dir)/cpp_type_generator.py',
-      '<(api_gen_dir)/cpp_util.py',
-      '<(api_gen_dir)/h_generator.py',
-      '<(api_gen_dir)/idl_schema.py',
-      '<(api_gen_dir)/json_schema.py',
-      '<(api_gen_dir)/model.py',
-      '<(api_gen_dir)/util_cc_helper.py',
-    ],
-    'schema_include_rules': [],
-  },
-  'actions': [
-    {
-      'action_name': 'genapi_bundle_schema',
-      'inputs': [
-        '<@(generator_files)',
-        '<@(schema_files)',
-        '<@(non_compiled_schema_files)',
-      ],
-      'outputs': [
-        '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/generated_schemas.h',
-        '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/generated_schemas.cc',
-      ],
-      'action': [
-        'python',
-        '<(api_gen)',
-        '--root=<(DEPTH)',
-        '--destdir=<(SHARED_INTERMEDIATE_DIR)',
-        '--namespace=<(root_namespace)',
-        '--generator=cpp-bundle-schema',
-        '--include-rules=<(schema_include_rules)',
-        '<@(schema_files)',
-        '<@(non_compiled_schema_files)',
-      ],
-      'message': 'Generating C++ API bundle code for schemas',
-      'process_outputs_as_sources': 1,
-      # Avoid running MIDL compiler on IDL input files.
-      'explicit_idl_action': 1,
-    },
-  ],
-  'include_dirs': [
-    '<(SHARED_INTERMEDIATE_DIR)',
-    '<(DEPTH)',
-  ],
-  'direct_dependent_settings': {
-    'include_dirs': [
-      '<(SHARED_INTERMEDIATE_DIR)',
-    ]
-  },
-  # This target exports a hard dependency because it generates header
-  # files.
-  'hard_dependency': 1,
-}
diff --git a/build/json_schema_bundle_registration_compile.gypi b/build/json_schema_bundle_registration_compile.gypi
deleted file mode 100644
index 8c5af4e8a02..00000000000
--- a/build/json_schema_bundle_registration_compile.gypi
+++ /dev/null
@@ -1,78 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-{
-  'variables': {
-    # When including this gypi, the following variables must be set:
-    #   schema_files:
-    #     An array of json or idl files that comprise the api model.
-    #   impl_dir_:
-    #     The root path of API implementations; also used for the
-    #     output location. (N.B. Named as such to prevent gyp from
-    #     expanding it as a relative path.)
-    #   root_namespace:
-    #     A Python string substituion pattern used to generate the C++
-    #     namespace for each API. Use %(namespace)s to replace with the API
-    #     namespace, like "toplevel::%(namespace)s_api".
-    #
-    # Functions and namespaces can be excluded by setting "nocompile" to true.
-    'api_gen_dir': '<(DEPTH)/tools/json_schema_compiler',
-    'api_gen': '<(api_gen_dir)/compiler.py',
-    'generator_files': [
-      '<(api_gen_dir)/cc_generator.py',
-      '<(api_gen_dir)/code.py',
-      '<(api_gen_dir)/compiler.py',
-      '<(api_gen_dir)/cpp_bundle_generator.py',
-      '<(api_gen_dir)/cpp_type_generator.py',
-      '<(api_gen_dir)/cpp_util.py',
-      '<(api_gen_dir)/h_generator.py',
-      '<(api_gen_dir)/idl_schema.py',
-      '<(api_gen_dir)/json_schema.py',
-      '<(api_gen_dir)/model.py',
-      '<(api_gen_dir)/util_cc_helper.py',
-    ],
-  },
-  'actions': [
-    {
-      # GN version: json_schema_api.gni
-      'action_name': 'genapi_bundle_registration',
-      'inputs': [
-        '<@(generator_files)',
-        '<@(schema_files)',
-        '<@(non_compiled_schema_files)',
-      ],
-      'outputs': [
-        '<(SHARED_INTERMEDIATE_DIR)/<(impl_dir_)/generated_api_registration.h',
-        '<(SHARED_INTERMEDIATE_DIR)/<(impl_dir_)/generated_api_registration.cc',
-      ],
-      'action': [
-        'python',
-        '<(api_gen)',
-        '--root=<(DEPTH)',
-        '--destdir=<(SHARED_INTERMEDIATE_DIR)',
-        '--namespace=<(root_namespace)',
-        '--generator=cpp-bundle-registration',
-        '--impl-dir=<(impl_dir_)',
-        '<@(schema_files)',
-        '<@(non_compiled_schema_files)',
-      ],
-      'message': 'Generating C++ API bundle code for function registration',
-      'process_outputs_as_sources': 1,
-      # Avoid running MIDL compiler on IDL input files.
-      'explicit_idl_action': 1,
-    },
-  ],
-  'include_dirs': [
-    '<(SHARED_INTERMEDIATE_DIR)',
-    '<(DEPTH)',
-  ],
-  'direct_dependent_settings': {
-    'include_dirs': [
-      '<(SHARED_INTERMEDIATE_DIR)',
-    ]
-  },
-  # This target exports a hard dependency because it generates header
-  # files.
-  'hard_dependency': 1,
-}
diff --git a/build/json_schema_compile.gypi b/build/json_schema_compile.gypi
deleted file mode 100644
index 6e5727a6ba4..00000000000
--- a/build/json_schema_compile.gypi
+++ /dev/null
@@ -1,123 +0,0 @@
-# Copyright (c) 2012 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-{
-  'variables': {
-    # When including this gypi, the following variables must be set:
-    #   schema_files:
-    #     An array of json or idl files that comprise the api model.
-    #   schema_include_rules (optional):
-    #     An array of paths to include when searching for referenced objects,
-    #     with the namespace separated by a :.
-    #     Example:
-    #       [ '/foo/bar:Foo::Bar::%(namespace)s' ]
-    #   cc_dir:
-    #     The directory to put the generated code in.
-    #   root_namespace:
-    #     A Python string substituion pattern used to generate the C++
-    #     namespace for each API. Use %(namespace)s to replace with the API
-    #     namespace, like "toplevel::%(namespace)s_api".
-    #
-    # Functions and namespaces can be excluded by setting "nocompile" to true.
-    'api_gen_dir': '<(DEPTH)/tools/json_schema_compiler',
-    'api_gen': '<(api_gen_dir)/compiler.py',
-    'schema_include_rules': [],
-  },
-  'rules': [
-    {
-      # GN version: json_schema_api.gni
-      'rule_name': 'genapi',
-      'msvs_external_rule': 1,
-      'extension': 'json',
-      'inputs': [
-        '<(api_gen_dir)/cc_generator.py',
-        '<(api_gen_dir)/code.py',
-        '<(api_gen_dir)/compiler.py',
-        '<(api_gen_dir)/cpp_generator.py',
-        '<(api_gen_dir)/cpp_type_generator.py',
-        '<(api_gen_dir)/cpp_util.py',
-        '<(api_gen_dir)/h_generator.py',
-        '<(api_gen_dir)/json_schema.py',
-        '<(api_gen_dir)/model.py',
-        '<(api_gen_dir)/util.cc',
-        '<(api_gen_dir)/util.h',
-        '<(api_gen_dir)/util_cc_helper.py',
-        # TODO(calamity): uncomment this when gyp on windows behaves like other
-        # platforms. List expansions of filepaths in inputs expand to different
-        # things.
-        # '<@(schema_files)',
-      ],
-      'outputs': [
-        '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).cc',
-        '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).h',
-      ],
-      'action': [
-        'python',
-        '<(api_gen)',
-        '<(RULE_INPUT_PATH)',
-        '--root=<(DEPTH)',
-        '--destdir=<(SHARED_INTERMEDIATE_DIR)',
-        '--namespace=<(root_namespace)',
-        '--generator=cpp',
-        '--include-rules=<(schema_include_rules)'
-      ],
-      'message': 'Generating C++ code from <(RULE_INPUT_PATH) json files',
-      'process_outputs_as_sources': 1,
-    },
-    {
-      'rule_name': 'genapi_idl',
-      'msvs_external_rule': 1,
-      'extension': 'idl',
-      'inputs': [
-        '<(api_gen_dir)/cc_generator.py',
-        '<(api_gen_dir)/code.py',
-        '<(api_gen_dir)/compiler.py',
-        '<(api_gen_dir)/cpp_generator.py',
-        '<(api_gen_dir)/cpp_type_generator.py',
-        '<(api_gen_dir)/cpp_util.py',
-        '<(api_gen_dir)/h_generator.py',
-        '<(api_gen_dir)/idl_schema.py',
-        '<(api_gen_dir)/model.py',
-        '<(api_gen_dir)/util.cc',
-        '<(api_gen_dir)/util.h',
-        '<(api_gen_dir)/util_cc_helper.py',
-        # TODO(calamity): uncomment this when gyp on windows behaves like other
-        # platforms. List expansions of filepaths in inputs expand to different
-        # things.
-        # '<@(schema_files)',
-      ],
-      'outputs': [
-        '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).cc',
-        '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).h',
-      ],
-      'action': [
-        'python',
-        '<(api_gen)',
-        '<(RULE_INPUT_PATH)',
-        '--root=<(DEPTH)',
-        '--destdir=<(SHARED_INTERMEDIATE_DIR)',
-        '--namespace=<(root_namespace)',
-        '--generator=cpp',
-        '--include-rules=<(schema_include_rules)'
-      ],
-      'message': 'Generating C++ code from <(RULE_INPUT_PATH) IDL files',
-      'process_outputs_as_sources': 1,
-    },
-  ],
-  'include_dirs': [
-    '<(SHARED_INTERMEDIATE_DIR)',
-    '<(DEPTH)',
-  ],
-  'dependencies':[
-    '<(DEPTH)/tools/json_schema_compiler/api_gen_util.gyp:api_gen_util',
-  ],
-  'direct_dependent_settings': {
-    'include_dirs': [
-      '<(SHARED_INTERMEDIATE_DIR)',
-    ]
-  },
-  # This target exports a hard dependency because it generates header
-  # files.
-  'hard_dependency': 1,
-}
diff --git a/build/json_to_struct.gypi b/build/json_to_struct.gypi
deleted file mode 100644
index 09c8e3e4574..00000000000
--- a/build/json_to_struct.gypi
+++ /dev/null
@@ -1,53 +0,0 @@
-# Copyright 2012 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-{
-  'variables': {
-    # When including this gypi, the following variables must be set:
-    #   schema_file: a json file that comprise the structure model.
-    #   namespace: the C++ namespace that all generated files go under
-    #   cc_dir: path to generated files
-    # Functions and namespaces can be excluded by setting "nocompile" to true.
-    'struct_gen_dir': '<(DEPTH)/tools/json_to_struct',
-    'struct_gen%': '<(struct_gen_dir)/json_to_struct.py',
-    'output_filename%': '<(RULE_INPUT_ROOT)',
-  },
-  'rules': [
-    {
-      # GN version: //tools/json_to_struct/json_to_struct.gni
-      'rule_name': 'genstaticinit',
-      'extension': 'json',
-      'inputs': [
-        '<(struct_gen)',
-        '<(struct_gen_dir)/element_generator.py',
-        '<(struct_gen_dir)/json_to_struct.py',
-        '<(struct_gen_dir)/struct_generator.py',
-        '<(schema_file)',
-      ],
-      'outputs': [
-        '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/<(output_filename).cc',
-        '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/<(output_filename).h',
-      ],
-      'action': [
-        'python',
-        '<(struct_gen)',
-        '<(RULE_INPUT_PATH)',
-        '--destbase=<(SHARED_INTERMEDIATE_DIR)',
-        '--destdir=<(cc_dir)',
-        '--namespace=<(namespace)',
-        '--schema=<(schema_file)',
-        '--output=<(output_filename)',
-      ],
-      'message': 'Generating C++ static initializers from <(RULE_INPUT_PATH)',
-      'process_outputs_as_sources': 1,
-    },
-  ],
-  'include_dirs': [
-    '<(SHARED_INTERMEDIATE_DIR)',
-    '<(DEPTH)',
-  ],
-  # This target exports a hard dependency because it generates header
-  # files.
-  'hard_dependency': 1,
-}
diff --git a/build/module_args/dart.gni b/build/module_args/dart.gni
deleted file mode 100644
index ee6b0387670..00000000000
--- a/build/module_args/dart.gni
+++ /dev/null
@@ -1,6 +0,0 @@
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This variable should point to the Dart SDK.
-dart_sdk_root = "//third_party/dart-sdk/dart-sdk"
diff --git a/build/module_args/mojo.gni b/build/module_args/mojo.gni
deleted file mode 100644
index fee9114a791..00000000000
--- a/build/module_args/mojo.gni
+++ /dev/null
@@ -1,16 +0,0 @@
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This variable should point to the parent directory of the Mojo SDK.
-mojo_sdk_root = "//"
-
-# To build the Mojo shell from source, set this variable to true. To use the
-# prebuilt shell, omit this variable or set it to false. Note that the prebuilt
-# shell will be used only on platforms for which it is published (currently
-# Linux and Android).
-mojo_build_mojo_shell_from_source = true
-
-# To build the network service from source, set this variable to true. To use
-# the prebuilt network service, omit this variable or set it to false.
-mojo_build_network_service_from_source = true
diff --git a/build/module_args/nacl.gni b/build/module_args/nacl.gni
deleted file mode 100644
index 61e0768e13a..00000000000
--- a/build/module_args/nacl.gni
+++ /dev/null
@@ -1,6 +0,0 @@
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Override nacl's build directory.
-nacl_shared_build_dir = "//build"
diff --git a/build/module_args/v8.gni b/build/module_args/v8.gni
deleted file mode 100644
index 8b5204c68ec..00000000000
--- a/build/module_args/v8.gni
+++ /dev/null
@@ -1,13 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-if (is_android) {
-  import("//build/config/android/config.gni")
-}
-
-# TODO(sky): nuke this. Temporary while sorting out http://crbug.com/465456.
-enable_correct_v8_arch = false
-
-v8_use_external_startup_data = !(is_chromeos || is_win)
-v8_extra_library_files = []
diff --git a/build/secondary/testing/gmock/BUILD.gn b/build/secondary/testing/gmock/BUILD.gn
deleted file mode 100644
index 4ec62245e6b..00000000000
--- a/build/secondary/testing/gmock/BUILD.gn
+++ /dev/null
@@ -1,54 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-config("gmock_config") {
-  # Gmock headers need to be able to find themselves.
-  include_dirs = [ "include" ]
-}
-
-static_library("gmock") {
-  # TODO http://crbug.com/412064 enable this flag all the time.
-  testonly = !is_component_build
-  sources = [
-    # Sources based on files in r173 of gmock.
-    "include/gmock/gmock-actions.h",
-    "include/gmock/gmock-cardinalities.h",
-    "include/gmock/gmock-generated-actions.h",
-    "include/gmock/gmock-generated-function-mockers.h",
-    "include/gmock/gmock-generated-matchers.h",
-    "include/gmock/gmock-generated-nice-strict.h",
-    "include/gmock/gmock-matchers.h",
-    "include/gmock/gmock-spec-builders.h",
-    "include/gmock/gmock.h",
-    "include/gmock/internal/gmock-generated-internal-utils.h",
-    "include/gmock/internal/gmock-internal-utils.h",
-    "include/gmock/internal/gmock-port.h",
-
-    #"src/gmock-all.cc",  # Not needed by our build.
-    "src/gmock-cardinalities.cc",
-    "src/gmock-internal-utils.cc",
-    "src/gmock-matchers.cc",
-    "src/gmock-spec-builders.cc",
-    "src/gmock.cc",
-  ]
-
-  # This project includes some stuff form gtest's guts.
-  include_dirs = [ "../gtest/include" ]
-
-  public_configs = [
-    ":gmock_config",
-    "//testing/gtest:gtest_config",
-  ]
-}
-
-static_library("gmock_main") {
-  # TODO http://crbug.com/412064 enable this flag all the time.
-  testonly = !is_component_build
-  sources = [
-    "src/gmock_main.cc",
-  ]
-  deps = [
-    ":gmock",
-  ]
-}
diff --git a/build/secondary/testing/gtest/BUILD.gn b/build/secondary/testing/gtest/BUILD.gn
deleted file mode 100644
index 073faec5629..00000000000
--- a/build/secondary/testing/gtest/BUILD.gn
+++ /dev/null
@@ -1,135 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-config("gtest_config") {
-  visibility = [
-    ":*",
-    "//testing/gmock:*",  # gmock also shares this config.
-  ]
-
-  defines = [
-    # In order to allow regex matches in gtest to be shared between Windows
-    # and other systems, we tell gtest to always use it's internal engine.
-    "GTEST_HAS_POSIX_RE=0",
-
-    # Chrome doesn't support / require C++11, yet.
-    "GTEST_LANG_CXX11=0",
-  ]
-
-  # Gtest headers need to be able to find themselves.
-  include_dirs = [ "include" ]
-
-  if (is_win) {
-    cflags = [ "/wd4800" ]  # Unused variable warning.
-  }
-
-  if (is_posix) {
-    defines += [
-      # gtest isn't able to figure out when RTTI is disabled for gcc
-      # versions older than 4.3.2, and assumes it's enabled.  Our Mac
-      # and Linux builds disable RTTI, and cannot guarantee that the
-      # compiler will be 4.3.2. or newer.  The Mac, for example, uses
-      # 4.2.1 as that is the latest available on that platform.  gtest
-      # must be instructed that RTTI is disabled here, and for any
-      # direct dependents that might include gtest headers.
-      "GTEST_HAS_RTTI=0",
-    ]
-  }
-
-  if (is_android) {
-    defines += [
-      # We want gtest features that use tr1::tuple, but we currently
-      # don't support the variadic templates used by libstdc++'s
-      # implementation. gtest supports this scenario by providing its
-      # own implementation but we must opt in to it.
-      "GTEST_USE_OWN_TR1_TUPLE=1",
-
-      # GTEST_USE_OWN_TR1_TUPLE only works if GTEST_HAS_TR1_TUPLE is set.
-      # gtest r625 made it so that GTEST_HAS_TR1_TUPLE is set to 0
-      # automatically on android, so it has to be set explicitly here.
-      "GTEST_HAS_TR1_TUPLE=1",
-    ]
-  }
-}
-
-config("gtest_direct_config") {
-  visibility = [ ":*" ]
-  defines = [ "UNIT_TEST" ]
-}
-
-static_library("gtest") {
-  # TODO http://crbug.com/412064 enable this flag all the time.
-  testonly = !is_component_build
-  sources = [
-    "include/gtest/gtest-death-test.h",
-    "include/gtest/gtest-message.h",
-    "include/gtest/gtest-param-test.h",
-    "include/gtest/gtest-printers.h",
-    "include/gtest/gtest-spi.h",
-    "include/gtest/gtest-test-part.h",
-    "include/gtest/gtest-typed-test.h",
-    "include/gtest/gtest.h",
-    "include/gtest/gtest_pred_impl.h",
-    "include/gtest/internal/gtest-death-test-internal.h",
-    "include/gtest/internal/gtest-filepath.h",
-    "include/gtest/internal/gtest-internal.h",
-    "include/gtest/internal/gtest-linked_ptr.h",
-    "include/gtest/internal/gtest-param-util-generated.h",
-    "include/gtest/internal/gtest-param-util.h",
-    "include/gtest/internal/gtest-port.h",
-    "include/gtest/internal/gtest-string.h",
-    "include/gtest/internal/gtest-tuple.h",
-    "include/gtest/internal/gtest-type-util.h",
-
-    #"gtest/src/gtest-all.cc",  # Not needed by our build.
-    "../multiprocess_func_list.cc",
-    "../multiprocess_func_list.h",
-    "../platform_test.h",
-    "src/gtest-death-test.cc",
-    "src/gtest-filepath.cc",
-    "src/gtest-internal-inl.h",
-    "src/gtest-port.cc",
-    "src/gtest-printers.cc",
-    "src/gtest-test-part.cc",
-    "src/gtest-typed-test.cc",
-    "src/gtest.cc",
-  ]
-
-  if (is_mac) {
-    sources += [
-      "../gtest_mac.h",
-      "../gtest_mac.mm",
-      "../platform_test_mac.mm",
-    ]
-  }
-
-  include_dirs = [ "." ]
-
-  all_dependent_configs = [ ":gtest_config" ]
-  public_configs = [ ":gtest_direct_config" ]
-
-  configs -= [ "//build/config/compiler:chromium_code" ]
-  configs += [ "//build/config/compiler:no_chromium_code" ]
-
-  config("gtest_warnings") {
-    if (is_win && is_clang) {
-      # The Mutex constructor initializer list in gtest-port.cc is incorrectly
-      # ordered. See
-      # https://groups.google.com/d/msg/googletestframework/S5uSV8L2TX8/U1FaTDa6J6sJ.
-      cflags = [ "-Wno-reorder" ]
-    }
-  }
-  configs += [ ":gtest_warnings" ]
-}
-
-source_set("gtest_main") {
-  # TODO http://crbug.com/412064 enable this flag all the time.
-  testonly = !is_component_build
-  sources = [
-    "src/gtest_main.cc",
-  ]
-  deps = [
-    ":gtest",
-  ]
-}
diff --git a/build/secondary/third_party/libjpeg_turbo/BUILD.gn b/build/secondary/third_party/libjpeg_turbo/BUILD.gn
deleted file mode 100644
index 62e60aed0db..00000000000
--- a/build/secondary/third_party/libjpeg_turbo/BUILD.gn
+++ /dev/null
@@ -1,221 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Do not use the targets in this file unless you need a certain libjpeg
-# implementation. Use the meta target //third_party:jpeg instead.
-
-import("//build/config/sanitizers/sanitizers.gni")
-
-if (current_cpu == "arm") {
-  import("//build/config/arm.gni")
-}
-
-if (current_cpu == "x86" || current_cpu == "x64") {
-  import("//third_party/yasm/yasm_assemble.gni")
-
-  yasm_assemble("simd_asm") {
-    defines = []
-
-    if (current_cpu == "x86") {
-      sources = [
-        "simd/jccolor-mmx.asm",
-        "simd/jccolor-sse2.asm",
-        "simd/jcgray-mmx.asm",
-        "simd/jcgray-sse2.asm",
-        "simd/jchuff-sse2.asm",
-        "simd/jcsample-mmx.asm",
-        "simd/jcsample-sse2.asm",
-        "simd/jdcolor-mmx.asm",
-        "simd/jdcolor-sse2.asm",
-        "simd/jdmerge-mmx.asm",
-        "simd/jdmerge-sse2.asm",
-        "simd/jdsample-mmx.asm",
-        "simd/jdsample-sse2.asm",
-        "simd/jfdctflt-3dn.asm",
-        "simd/jfdctflt-sse.asm",
-        "simd/jfdctfst-mmx.asm",
-        "simd/jfdctfst-sse2.asm",
-        "simd/jfdctint-mmx.asm",
-        "simd/jfdctint-sse2.asm",
-        "simd/jidctflt-3dn.asm",
-        "simd/jidctflt-sse.asm",
-        "simd/jidctflt-sse2.asm",
-        "simd/jidctfst-mmx.asm",
-        "simd/jidctfst-sse2.asm",
-        "simd/jidctint-mmx.asm",
-        "simd/jidctint-sse2.asm",
-        "simd/jidctred-mmx.asm",
-        "simd/jidctred-sse2.asm",
-        "simd/jquant-3dn.asm",
-        "simd/jquant-mmx.asm",
-        "simd/jquant-sse.asm",
-        "simd/jquantf-sse2.asm",
-        "simd/jquanti-sse2.asm",
-        "simd/jsimdcpu.asm",
-      ]
-      defines += [
-        "__x86__",
-        "PIC",
-      ]
-    } else if (current_cpu == "x64") {
-      sources = [
-        "simd/jccolor-sse2-64.asm",
-        "simd/jcgray-sse2-64.asm",
-        "simd/jchuff-sse2-64.asm",
-        "simd/jcsample-sse2-64.asm",
-        "simd/jdcolor-sse2-64.asm",
-        "simd/jdmerge-sse2-64.asm",
-        "simd/jdsample-sse2-64.asm",
-        "simd/jfdctflt-sse-64.asm",
-        "simd/jfdctfst-sse2-64.asm",
-        "simd/jfdctint-sse2-64.asm",
-        "simd/jidctflt-sse2-64.asm",
-        "simd/jidctfst-sse2-64.asm",
-        "simd/jidctint-sse2-64.asm",
-        "simd/jidctred-sse2-64.asm",
-        "simd/jquantf-sse2-64.asm",
-        "simd/jquanti-sse2-64.asm",
-      ]
-      defines += [
-        "__x86_64__",
-        "PIC",
-      ]
-    }
-
-    if (is_win) {
-      defines += [ "MSVC" ]
-      include_dirs = [ "win" ]
-      if (current_cpu == "x86") {
-        defines += [ "WIN32" ]
-      } else {
-        defines += [ "WIN64" ]
-      }
-    } else if (is_mac) {
-      defines += [ "MACHO" ]
-      include_dirs = [ "mac" ]
-    } else if (is_linux || is_android) {
-      defines += [ "ELF" ]
-      include_dirs = [ "linux" ]
-    }
-  }
-}
-
-source_set("simd") {
-  if (current_cpu == "x86") {
-    deps = [
-      ":simd_asm",
-    ]
-    sources = [
-      "simd/jsimd_i386.c",
-    ]
-    if (is_win) {
-      cflags = [ "/wd4245" ]
-    }
-  } else if (current_cpu == "x64") {
-    deps = [
-      ":simd_asm",
-    ]
-    sources = [
-      "simd/jsimd_x86_64.c",
-    ]
-  } else if (current_cpu == "arm" && arm_version >= 7 &&
-             (arm_use_neon || arm_optionally_use_neon)) {
-    sources = [
-      "simd/jsimd_arm.c",
-      "simd/jsimd_arm_neon.S",
-    ]
-  } else {
-    sources = [
-      "jsimd_none.c",
-    ]
-  }
-  if (is_win) {
-    cflags = [ "/wd4245" ]
-  }
-}
-
-config("libjpeg_config") {
-  include_dirs = [ "." ]
-}
-
-source_set("libjpeg") {
-  sources = [
-    "jcapimin.c",
-    "jcapistd.c",
-    "jccoefct.c",
-    "jccolor.c",
-    "jcdctmgr.c",
-    "jchuff.c",
-    "jchuff.h",
-    "jcinit.c",
-    "jcmainct.c",
-    "jcmarker.c",
-    "jcmaster.c",
-    "jcomapi.c",
-    "jconfig.h",
-    "jcparam.c",
-    "jcphuff.c",
-    "jcprepct.c",
-    "jcsample.c",
-    "jdapimin.c",
-    "jdapistd.c",
-    "jdatadst.c",
-    "jdatasrc.c",
-    "jdcoefct.c",
-    "jdcolor.c",
-    "jdct.h",
-    "jddctmgr.c",
-    "jdhuff.c",
-    "jdhuff.h",
-    "jdinput.c",
-    "jdmainct.c",
-    "jdmarker.c",
-    "jdmaster.c",
-    "jdmerge.c",
-    "jdphuff.c",
-    "jdpostct.c",
-    "jdsample.c",
-    "jerror.c",
-    "jerror.h",
-    "jfdctflt.c",
-    "jfdctfst.c",
-    "jfdctint.c",
-    "jidctflt.c",
-    "jidctfst.c",
-    "jidctint.c",
-    "jidctred.c",
-    "jinclude.h",
-    "jmemmgr.c",
-    "jmemnobs.c",
-    "jmemsys.h",
-    "jmorecfg.h",
-    "jpegint.h",
-    "jpeglib.h",
-    "jpeglibmangler.h",
-    "jquant1.c",
-    "jquant2.c",
-    "jutils.c",
-    "jversion.h",
-  ]
-
-  defines = [
-    "WITH_SIMD",
-    "NO_GETENV",
-  ]
-
-  configs -= [ "//build/config/compiler:chromium_code" ]
-  configs += [ "//build/config/compiler:no_chromium_code" ]
-
-  public_configs = [ ":libjpeg_config" ]
-
-  # MemorySanitizer doesn't support assembly code, so keep it disabled in
-  # MSan builds for now.
-  if (is_msan) {
-    sources += [ "jsimd_none.c" ]
-  } else {
-    deps = [
-      ":simd",
-    ]
-  }
-}
diff --git a/build/secondary/third_party/libsrtp/BUILD.gn b/build/secondary/third_party/libsrtp/BUILD.gn
deleted file mode 100644
index 7601bea0d64..00000000000
--- a/build/secondary/third_party/libsrtp/BUILD.gn
+++ /dev/null
@@ -1,391 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-declare_args() {
-  use_system_libsrtp = false
-  use_srtp_boringssl = true
-}
-
-config("libsrtp_config") {
-  defines = [
-    "HAVE_CONFIG_H",
-    "HAVE_STDLIB_H",
-    "HAVE_STRING_H",
-    "TESTAPP_SOURCE",
-  ]
-
-  include_dirs = [
-    "config",
-    "srtp/include",
-    "srtp/crypto/include",
-  ]
-
-  if (use_srtp_boringssl) {
-    defines += [ "OPENSSL" ]
-  }
-
-  if (is_posix) {
-    defines += [
-      "HAVE_INT16_T",
-      "HAVE_INT32_T",
-      "HAVE_INT8_T",
-      "HAVE_UINT16_T",
-      "HAVE_UINT32_T",
-      "HAVE_UINT64_T",
-      "HAVE_UINT8_T",
-      "HAVE_STDINT_H",
-      "HAVE_INTTYPES_H",
-      "HAVE_NETINET_IN_H",
-      "HAVE_ARPA_INET_H",
-      "HAVE_UNISTD_H",
-    ]
-    cflags = [ "-Wno-unused-variable" ]
-  }
-
-  if (is_win) {
-    defines += [
-      "HAVE_BYTESWAP_METHODS_H",
-
-      # All Windows architectures are this way.
-      "SIZEOF_UNSIGNED_LONG=4",
-      "SIZEOF_UNSIGNED_LONG_LONG=8",
-    ]
-  }
-
-  if (current_cpu == "x64" || current_cpu == "x86" || current_cpu == "arm") {
-    defines += [
-      # TODO(leozwang): CPU_RISC doesn"t work properly on android/arm
-      # platform for unknown reasons, need to investigate the root cause
-      # of it. CPU_RISC is used for optimization only, and CPU_CISC should
-      # just work just fine, it has been tested on android/arm with srtp
-      # test applications and libjingle.
-      "CPU_CISC",
-    ]
-  }
-
-  if (current_cpu == "mipsel") {
-    defines += [ "CPU_RISC" ]
-  }
-}
-
-config("system_libsrtp_config") {
-  defines = [ "USE_SYSTEM_LIBSRTP" ]
-  include_dirs = [ "/usr/include/srtp" ]
-}
-
-if (use_system_libsrtp) {
-  group("libsrtp") {
-    public_configs = [
-      ":libsrtp_config",
-      ":system_libsrtp_config",
-    ]
-    libs = [ "-lsrtp" ]
-  }
-} else {
-  static_library("libsrtp") {
-    configs -= [ "//build/config/compiler:chromium_code" ]
-    configs += [ "//build/config/compiler:no_chromium_code" ]
-    public_configs = [ ":libsrtp_config" ]
-
-    sources = [
-      # includes
-      "srtp/include/ekt.h",
-      "srtp/include/getopt_s.h",
-      "srtp/include/rtp.h",
-      "srtp/include/rtp_priv.h",
-      "srtp/include/srtp.h",
-      "srtp/include/srtp_priv.h",
-      "srtp/include/ut_sim.h",
-
-      # headers
-      "srtp/crypto/include/aes.h",
-      "srtp/crypto/include/aes_cbc.h",
-      "srtp/crypto/include/aes_icm.h",
-      "srtp/crypto/include/alloc.h",
-      "srtp/crypto/include/auth.h",
-      "srtp/crypto/include/cipher.h",
-      "srtp/crypto/include/crypto.h",
-      "srtp/crypto/include/crypto_kernel.h",
-      "srtp/crypto/include/crypto_math.h",
-      "srtp/crypto/include/crypto_types.h",
-      "srtp/crypto/include/cryptoalg.h",
-      "srtp/crypto/include/datatypes.h",
-      "srtp/crypto/include/err.h",
-      "srtp/crypto/include/gf2_8.h",
-      "srtp/crypto/include/hmac.h",
-      "srtp/crypto/include/integers.h",
-      "srtp/crypto/include/kernel_compat.h",
-      "srtp/crypto/include/key.h",
-      "srtp/crypto/include/null_auth.h",
-      "srtp/crypto/include/null_cipher.h",
-      "srtp/crypto/include/prng.h",
-      "srtp/crypto/include/rand_source.h",
-      "srtp/crypto/include/rdb.h",
-      "srtp/crypto/include/rdbx.h",
-      "srtp/crypto/include/sha1.h",
-      "srtp/crypto/include/stat.h",
-      "srtp/crypto/include/xfm.h",
-
-      # sources
-      "srtp/crypto/cipher/aes.c",
-      "srtp/crypto/cipher/aes_cbc.c",
-      "srtp/crypto/cipher/aes_icm.c",
-      "srtp/crypto/cipher/cipher.c",
-      "srtp/crypto/cipher/null_cipher.c",
-      "srtp/crypto/hash/auth.c",
-      "srtp/crypto/hash/hmac.c",
-      "srtp/crypto/hash/null_auth.c",
-      "srtp/crypto/hash/sha1.c",
-      "srtp/crypto/kernel/alloc.c",
-      "srtp/crypto/kernel/crypto_kernel.c",
-      "srtp/crypto/kernel/err.c",
-      "srtp/crypto/kernel/key.c",
-      "srtp/crypto/math/datatypes.c",
-      "srtp/crypto/math/gf2_8.c",
-      "srtp/crypto/math/stat.c",
-      "srtp/crypto/replay/rdb.c",
-      "srtp/crypto/replay/rdbx.c",
-      "srtp/crypto/replay/ut_sim.c",
-      "srtp/crypto/rng/ctr_prng.c",
-      "srtp/crypto/rng/prng.c",
-      "srtp/crypto/rng/rand_source.c",
-      "srtp/srtp/ekt.c",
-      "srtp/srtp/srtp.c",
-    ]
-
-    if (is_clang) {
-      cflags = [ "-Wno-implicit-function-declaration" ]
-    }
-
-    if (use_srtp_boringssl) {
-      deps = [
-        "//third_party/boringssl:boringssl",
-      ]
-      public_deps = [
-        "//third_party/boringssl:boringssl",
-      ]
-      sources -= [
-        "srtp/crypto/cipher/aes_cbc.c",
-        "srtp/crypto/cipher/aes_icm.c",
-        "srtp/crypto/hash/hmac.c",
-        "srtp/crypto/hash/sha1.c",
-        "srtp/crypto/rng/ctr_prng.c",
-        "srtp/crypto/rng/prng.c",
-      ]
-      sources += [
-        "srtp/crypto/cipher/aes_gcm_ossl.c",
-        "srtp/crypto/cipher/aes_icm_ossl.c",
-        "srtp/crypto/hash/hmac_ossl.c",
-        "srtp/crypto/include/aes_gcm_ossl.h",
-        "srtp/crypto/include/aes_icm_ossl.h",
-      ]
-    }
-  }
-
-  # TODO(GYP): A bunch of these tests don't compile (in gyp either). They're
-  # not very broken, so could probably be made to work if it's useful.
-  if (!is_win) {
-    executable("rdbx_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/include/getopt_s.h",
-        "srtp/test/getopt_s.c",
-        "srtp/test/rdbx_driver.c",
-      ]
-    }
-
-    executable("srtp_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/include/getopt_s.h",
-        "srtp/include/srtp_priv.h",
-        "srtp/test/getopt_s.c",
-        "srtp/test/srtp_driver.c",
-      ]
-    }
-
-    executable("roc_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/include/rdbx.h",
-        "srtp/include/ut_sim.h",
-        "srtp/test/roc_driver.c",
-      ]
-    }
-
-    executable("replay_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/include/rdbx.h",
-        "srtp/include/ut_sim.h",
-        "srtp/test/replay_driver.c",
-      ]
-    }
-
-    executable("rtpw") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/include/datatypes.h",
-        "srtp/include/getopt_s.h",
-        "srtp/include/rtp.h",
-        "srtp/include/srtp.h",
-        "srtp/test/getopt_s.c",
-        "srtp/test/rtp.c",
-        "srtp/test/rtpw.c",
-      ]
-      if (is_android) {
-        defines = [ "HAVE_SYS_SOCKET_H" ]
-      }
-      if (is_clang) {
-        cflags = [ "-Wno-implicit-function-declaration" ]
-      }
-    }
-
-    executable("srtp_test_cipher_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/cipher_driver.c",
-        "srtp/include/getopt_s.h",
-        "srtp/test/getopt_s.c",
-      ]
-    }
-
-    executable("srtp_test_datatypes_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/datatypes_driver.c",
-      ]
-    }
-
-    executable("srtp_test_stat_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/stat_driver.c",
-      ]
-    }
-
-    executable("srtp_test_sha1_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/sha1_driver.c",
-      ]
-    }
-
-    executable("srtp_test_kernel_driver") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/kernel_driver.c",
-        "srtp/include/getopt_s.h",
-        "srtp/test/getopt_s.c",
-      ]
-    }
-
-    executable("srtp_test_aes_calc") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/aes_calc.c",
-      ]
-    }
-
-    executable("srtp_test_rand_gen") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/rand_gen.c",
-        "srtp/include/getopt_s.h",
-        "srtp/test/getopt_s.c",
-      ]
-    }
-
-    executable("srtp_test_rand_gen_soak") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/rand_gen_soak.c",
-        "srtp/include/getopt_s.h",
-        "srtp/test/getopt_s.c",
-      ]
-    }
-
-    executable("srtp_test_env") {
-      configs -= [ "//build/config/compiler:chromium_code" ]
-      configs += [ "//build/config/compiler:no_chromium_code" ]
-      deps = [
-        ":libsrtp",
-      ]
-      sources = [
-        "srtp/crypto/test/env.c",
-      ]
-    }
-
-    group("srtp_runtest") {
-      deps = [
-        ":rdbx_driver",
-        ":srtp_driver",
-        ":roc_driver",
-        ":replay_driver",
-        ":rtpw",
-        ":srtp_test_cipher_driver",
-        ":srtp_test_datatypes_driver",
-        ":srtp_test_stat_driver",
-        ":srtp_test_sha1_driver",
-        ":srtp_test_kernel_driver",
-        ":srtp_test_aes_calc",
-        ":srtp_test_rand_gen",
-        ":srtp_test_rand_gen_soak",
-        ":srtp_test_env",
-      ]
-    }
-  }
-}
diff --git a/build/secondary/third_party/nss/BUILD.gn b/build/secondary/third_party/nss/BUILD.gn
deleted file mode 100644
index 25d449e14dc..00000000000
--- a/build/secondary/third_party/nss/BUILD.gn
+++ /dev/null
@@ -1,1211 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import("//build/config/linux/pkg_config.gni")
-
-if (is_linux) {
-  # This is a dependency on NSS with no libssl. On Linux we use a built-in SSL
-  # library but the system NSS libraries. Non-Linux platforms using NSS use the
-  # hermetic one in //third_party/nss.
-  #
-  # Generally you should depend on //crypto:platform instead of using this
-  # config since that will properly pick up NSS or OpenSSL depending on
-  # platform and build config.
-  pkg_config("system_nss_no_ssl_config") {
-    packages = [ "nss" ]
-    extra_args = [
-      "-v",
-      "-lssl3",
-    ]
-  }
-} else {
-  include_nss_root_certs = is_ios
-  include_nss_libpkix = is_ios
-
-  config("nspr_config") {
-    defines = [ "NO_NSPR_10_SUPPORT" ]
-    include_dirs = [
-      "nspr/pr/include",
-      "nspr/lib/ds",
-      "nspr/lib/libc/include",
-    ]
-
-    if (component_mode != "shared_library") {
-      defines += [ "NSPR_STATIC" ]
-    }
-  }
-
-  component("nspr") {
-    output_name = "crnspr"
-    sources = [
-      "nspr/lib/ds/plarena.c",
-      "nspr/lib/ds/plarena.h",
-      "nspr/lib/ds/plarenas.h",
-      "nspr/lib/ds/plhash.c",
-      "nspr/lib/ds/plhash.h",
-      "nspr/lib/libc/include/plbase64.h",
-      "nspr/lib/libc/include/plerror.h",
-      "nspr/lib/libc/include/plgetopt.h",
-      "nspr/lib/libc/include/plstr.h",
-      "nspr/lib/libc/src/base64.c",
-      "nspr/lib/libc/src/plerror.c",
-      "nspr/lib/libc/src/plgetopt.c",
-      "nspr/lib/libc/src/strcase.c",
-      "nspr/lib/libc/src/strcat.c",
-      "nspr/lib/libc/src/strchr.c",
-      "nspr/lib/libc/src/strcmp.c",
-      "nspr/lib/libc/src/strcpy.c",
-      "nspr/lib/libc/src/strdup.c",
-      "nspr/lib/libc/src/strlen.c",
-      "nspr/lib/libc/src/strpbrk.c",
-      "nspr/lib/libc/src/strstr.c",
-      "nspr/lib/libc/src/strtok.c",
-      "nspr/pr/include/md/_darwin.cfg",
-      "nspr/pr/include/md/_darwin.h",
-      "nspr/pr/include/md/_pcos.h",
-      "nspr/pr/include/md/_pth.h",
-      "nspr/pr/include/md/_unix_errors.h",
-      "nspr/pr/include/md/_unixos.h",
-      "nspr/pr/include/md/_win32_errors.h",
-      "nspr/pr/include/md/_win95.cfg",
-      "nspr/pr/include/md/_win95.h",
-      "nspr/pr/include/md/prosdep.h",
-      "nspr/pr/include/nspr.h",
-      "nspr/pr/include/obsolete/pralarm.h",
-      "nspr/pr/include/obsolete/probslet.h",
-      "nspr/pr/include/obsolete/protypes.h",
-      "nspr/pr/include/obsolete/prsem.h",
-      "nspr/pr/include/pratom.h",
-      "nspr/pr/include/prbit.h",
-      "nspr/pr/include/prclist.h",
-      "nspr/pr/include/prcmon.h",
-      "nspr/pr/include/prcountr.h",
-      "nspr/pr/include/prcpucfg.h",
-      "nspr/pr/include/prcvar.h",
-      "nspr/pr/include/prdtoa.h",
-      "nspr/pr/include/prenv.h",
-      "nspr/pr/include/prerr.h",
-      "nspr/pr/include/prerror.h",
-      "nspr/pr/include/prinet.h",
-      "nspr/pr/include/prinit.h",
-      "nspr/pr/include/prinrval.h",
-      "nspr/pr/include/prio.h",
-      "nspr/pr/include/pripcsem.h",
-      "nspr/pr/include/private/pprio.h",
-      "nspr/pr/include/private/pprmwait.h",
-      "nspr/pr/include/private/pprthred.h",
-      "nspr/pr/include/private/primpl.h",
-      "nspr/pr/include/private/prpriv.h",
-      "nspr/pr/include/prlink.h",
-      "nspr/pr/include/prlock.h",
-      "nspr/pr/include/prlog.h",
-      "nspr/pr/include/prlong.h",
-      "nspr/pr/include/prmem.h",
-      "nspr/pr/include/prmon.h",
-      "nspr/pr/include/prmwait.h",
-      "nspr/pr/include/prnetdb.h",
-      "nspr/pr/include/prolock.h",
-      "nspr/pr/include/prpdce.h",
-      "nspr/pr/include/prprf.h",
-      "nspr/pr/include/prproces.h",
-      "nspr/pr/include/prrng.h",
-      "nspr/pr/include/prrwlock.h",
-      "nspr/pr/include/prshm.h",
-      "nspr/pr/include/prshma.h",
-      "nspr/pr/include/prsystem.h",
-      "nspr/pr/include/prthread.h",
-      "nspr/pr/include/prtime.h",
-      "nspr/pr/include/prtpool.h",
-      "nspr/pr/include/prtrace.h",
-      "nspr/pr/include/prtypes.h",
-      "nspr/pr/include/prvrsion.h",
-      "nspr/pr/include/prwin16.h",
-      "nspr/pr/src/io/prdir.c",
-      "nspr/pr/src/io/prfdcach.c",
-      "nspr/pr/src/io/prfile.c",
-      "nspr/pr/src/io/prio.c",
-      "nspr/pr/src/io/priometh.c",
-      "nspr/pr/src/io/pripv6.c",
-      "nspr/pr/src/io/prlayer.c",
-      "nspr/pr/src/io/prlog.c",
-      "nspr/pr/src/io/prmapopt.c",
-      "nspr/pr/src/io/prmmap.c",
-      "nspr/pr/src/io/prmwait.c",
-      "nspr/pr/src/io/prpolevt.c",
-      "nspr/pr/src/io/prprf.c",
-      "nspr/pr/src/io/prscanf.c",
-      "nspr/pr/src/io/prsocket.c",
-      "nspr/pr/src/io/prstdio.c",
-      "nspr/pr/src/linking/prlink.c",
-      "nspr/pr/src/malloc/prmalloc.c",
-      "nspr/pr/src/malloc/prmem.c",
-      "nspr/pr/src/md/prosdep.c",
-      "nspr/pr/src/md/unix/darwin.c",
-      "nspr/pr/src/md/unix/os_Darwin.s",
-      "nspr/pr/src/md/unix/unix.c",
-      "nspr/pr/src/md/unix/unix_errors.c",
-      "nspr/pr/src/md/unix/uxproces.c",
-      "nspr/pr/src/md/unix/uxrng.c",
-      "nspr/pr/src/md/unix/uxshm.c",
-      "nspr/pr/src/md/unix/uxwrap.c",
-      "nspr/pr/src/md/windows/ntgc.c",
-      "nspr/pr/src/md/windows/ntinrval.c",
-      "nspr/pr/src/md/windows/ntmisc.c",
-      "nspr/pr/src/md/windows/ntsec.c",
-      "nspr/pr/src/md/windows/ntsem.c",
-      "nspr/pr/src/md/windows/w32ipcsem.c",
-      "nspr/pr/src/md/windows/w32poll.c",
-      "nspr/pr/src/md/windows/w32rng.c",
-      "nspr/pr/src/md/windows/w32shm.c",
-      "nspr/pr/src/md/windows/w95cv.c",
-      "nspr/pr/src/md/windows/w95dllmain.c",
-      "nspr/pr/src/md/windows/w95io.c",
-      "nspr/pr/src/md/windows/w95sock.c",
-      "nspr/pr/src/md/windows/w95thred.c",
-      "nspr/pr/src/md/windows/win32_errors.c",
-      "nspr/pr/src/memory/prseg.c",
-      "nspr/pr/src/memory/prshm.c",
-      "nspr/pr/src/memory/prshma.c",
-      "nspr/pr/src/misc/pralarm.c",
-      "nspr/pr/src/misc/pratom.c",
-      "nspr/pr/src/misc/praton.c",
-      "nspr/pr/src/misc/prcountr.c",
-      "nspr/pr/src/misc/prdtoa.c",
-      "nspr/pr/src/misc/prenv.c",
-      "nspr/pr/src/misc/prerr.c",
-      "nspr/pr/src/misc/prerror.c",
-      "nspr/pr/src/misc/prerrortable.c",
-      "nspr/pr/src/misc/prinit.c",
-      "nspr/pr/src/misc/prinrval.c",
-      "nspr/pr/src/misc/pripc.c",
-      "nspr/pr/src/misc/pripcsem.c",
-      "nspr/pr/src/misc/prlog2.c",
-      "nspr/pr/src/misc/prlong.c",
-      "nspr/pr/src/misc/prnetdb.c",
-      "nspr/pr/src/misc/prolock.c",
-      "nspr/pr/src/misc/prrng.c",
-      "nspr/pr/src/misc/prsystem.c",
-      "nspr/pr/src/misc/prthinfo.c",
-      "nspr/pr/src/misc/prtime.c",
-      "nspr/pr/src/misc/prtpool.c",
-      "nspr/pr/src/misc/prtrace.c",
-      "nspr/pr/src/pthreads/ptio.c",
-      "nspr/pr/src/pthreads/ptmisc.c",
-      "nspr/pr/src/pthreads/ptsynch.c",
-      "nspr/pr/src/pthreads/ptthread.c",
-      "nspr/pr/src/threads/combined/prucpu.c",
-      "nspr/pr/src/threads/combined/prucv.c",
-      "nspr/pr/src/threads/combined/prulock.c",
-      "nspr/pr/src/threads/combined/prustack.c",
-      "nspr/pr/src/threads/combined/pruthr.c",
-      "nspr/pr/src/threads/prcmon.c",
-      "nspr/pr/src/threads/prcthr.c",
-      "nspr/pr/src/threads/prdump.c",
-      "nspr/pr/src/threads/prmon.c",
-      "nspr/pr/src/threads/prrwlock.c",
-      "nspr/pr/src/threads/prsem.c",
-      "nspr/pr/src/threads/prtpd.c",
-    ]
-
-    public_configs = [ ":nspr_config" ]
-
-    configs -= [ "//build/config/compiler:chromium_code" ]
-    if (is_win) {
-      configs -= [
-        "//build/config/win:unicode",  # Requires 8-bit mode.
-        "//build/config/win:lean_and_mean",  # Won"t compile with lean and mean.
-      ]
-    }
-    configs += [
-      "//build/config/compiler:no_chromium_code",
-      "//build/config/compiler:no_size_t_to_int_warning",
-    ]
-
-    cflags = []
-    defines = [
-      "_NSPR_BUILD_",
-      "FORCE_PR_LOG",
-    ]
-
-    include_dirs = [ "nspr/pr/include/private" ]
-
-    if (is_win) {
-      cflags = [ "/wd4554" ]  # Check precidence.
-      defines += [
-        "XP_PC",
-        "WIN32",
-        "WIN95",
-        "_PR_GLOBAL_THREADS_ONLY",
-        "_CRT_SECURE_NO_WARNINGS",
-      ]
-    } else {
-      sources -= [
-        "nspr/pr/src/md/windows/ntgc.c",
-        "nspr/pr/src/md/windows/ntinrval.c",
-        "nspr/pr/src/md/windows/ntmisc.c",
-        "nspr/pr/src/md/windows/ntsec.c",
-        "nspr/pr/src/md/windows/ntsem.c",
-        "nspr/pr/src/md/windows/w32ipcsem.c",
-        "nspr/pr/src/md/windows/w32poll.c",
-        "nspr/pr/src/md/windows/w32rng.c",
-        "nspr/pr/src/md/windows/w32shm.c",
-        "nspr/pr/src/md/windows/w95cv.c",
-        "nspr/pr/src/md/windows/w95dllmain.c",
-        "nspr/pr/src/md/windows/w95io.c",
-        "nspr/pr/src/md/windows/w95sock.c",
-        "nspr/pr/src/md/windows/w95thred.c",
-        "nspr/pr/src/md/windows/win32_errors.c",
-        "nspr/pr/src/threads/combined/prucpu.c",
-        "nspr/pr/src/threads/combined/prucv.c",
-        "nspr/pr/src/threads/combined/prulock.c",
-        "nspr/pr/src/threads/combined/prustack.c",
-        "nspr/pr/src/threads/combined/pruthr.c",
-      ]
-    }
-
-    if (!is_posix) {
-      sources -= [
-        "nspr/pr/src/md/unix/darwin.c",
-        "nspr/pr/src/md/unix/os_Darwin.s",
-        "nspr/pr/src/md/unix/unix.c",
-        "nspr/pr/src/md/unix/unix_errors.c",
-        "nspr/pr/src/md/unix/uxproces.c",
-        "nspr/pr/src/md/unix/uxrng.c",
-        "nspr/pr/src/md/unix/uxshm.c",
-        "nspr/pr/src/md/unix/uxwrap.c",
-        "nspr/pr/src/pthreads/ptio.c",
-        "nspr/pr/src/pthreads/ptmisc.c",
-        "nspr/pr/src/pthreads/ptsynch.c",
-        "nspr/pr/src/pthreads/ptthread.c",
-      ]
-    }
-
-    if (current_cpu == "x86") {
-      defines += [ "_X86_" ]
-    } else if (current_cpu == "x64") {
-      defines += [ "_AMD64_" ]
-    }
-
-    if (is_mac || is_ios) {
-      sources -= [
-        "nspr/pr/src/io/prdir.c",
-        "nspr/pr/src/io/prfile.c",
-        "nspr/pr/src/io/prio.c",
-        "nspr/pr/src/io/prsocket.c",
-        "nspr/pr/src/misc/pripcsem.c",
-        "nspr/pr/src/threads/prcthr.c",
-        "nspr/pr/src/threads/prdump.c",
-        "nspr/pr/src/threads/prmon.c",
-        "nspr/pr/src/threads/prsem.c",
-      ]
-      defines += [
-        "XP_UNIX",
-        "DARWIN",
-        "XP_MACOSX",
-        "_PR_PTHREADS",
-        "HAVE_BSD_FLOCK",
-        "HAVE_DLADDR",
-        "HAVE_LCHOWN",
-        "HAVE_SOCKLEN_T",
-        "HAVE_STRERROR",
-      ]
-    }
-
-    if (is_mac) {
-      defines += [ "HAVE_CRT_EXTERNS_H" ]
-      libs = [
-        "CoreFoundation.framework",
-        "CoreServices.framework",
-      ]
-    }
-
-    if (is_clang) {
-      cflags += [
-        # nspr uses a bunch of deprecated functions (NSLinkModule etc) in
-        # prlink.c on mac.
-        "-Wno-deprecated-declarations",
-
-        # nspr passes "const char*" through "void*".
-        "-Wno-incompatible-pointer-types",
-
-        # nspr passes "int*" through "unsigned int*".
-        "-Wno-pointer-sign",
-      ]
-
-      # nspr uses assert(!"foo") instead of assert(false && "foo").
-      configs -= [ "//build/config/clang:extra_warnings" ]
-    }
-  }
-
-  component("nss") {
-    output_name = "crnss"
-    sources = [
-      # Ensure at least one object file is produced, so that MSVC does not
-      # warn when creating the static/shared library. See the note for
-      # the "nssckbi" target for why the "nss" target was split as such.
-      "nss/lib/nss/nssver.c",
-    ]
-
-    public_deps = [
-      ":nss_static",
-    ]
-
-    if (include_nss_root_certs) {
-      public_deps += [ ":nssckbi" ]
-    }
-
-    if (component_mode == "shared_library") {
-      if (is_mac) {
-        ldflags = [ "-all_load" ]
-      } else if (is_win) {
-        # Pass the def file to the linker.
-        ldflags =
-            [ "/DEF:" + rebase_path("nss/exports_win.def", root_build_dir) ]
-      }
-    }
-  }
-
-  config("nssckbi_config") {
-    include_dirs = [ "nss/lib/ckfw/builtins" ]
-  }
-
-  # This is really more of a pseudo-target to work around the fact that
-  # a single static_library target cannot contain two object files of the
-  # same name (hash.o / hash.obj). Logically, this is part of the
-  # "nss_static" target. By separating it out, it creates a possible
-  # circular dependency between "nss_static" and "nssckbi" when
-  # "exclude_nss_root_certs" is not specified, as "nss_static" depends on
-  # the "builtinsC_GetFunctionList" exported by this target. This is an
-  # artifact of how NSS is being statically built, which is not an
-  # officially supported configuration - normally, "nssckbi.dll/so" would
-  # depend on libnss3.dll/so, and the higher layer caller would instruct
-  # libnss3.dll to dynamically load nssckbi.dll, breaking the circle.
-  #
-  # TODO(rsleevi): http://crbug.com/128134 - Break the circular dependency
-  # without requiring nssckbi to be built as a shared library.
-  source_set("nssckbi") {
-    visibility = [ ":nss" ]  # This target is internal implementation detail.
-
-    sources = [
-      "nss/lib/ckfw/builtins/anchor.c",
-      "nss/lib/ckfw/builtins/bfind.c",
-      "nss/lib/ckfw/builtins/binst.c",
-      "nss/lib/ckfw/builtins/bobject.c",
-      "nss/lib/ckfw/builtins/bsession.c",
-      "nss/lib/ckfw/builtins/bslot.c",
-      "nss/lib/ckfw/builtins/btoken.c",
-      "nss/lib/ckfw/builtins/builtins.h",
-      "nss/lib/ckfw/builtins/certdata.c",
-      "nss/lib/ckfw/builtins/ckbiver.c",
-      "nss/lib/ckfw/builtins/constants.c",
-      "nss/lib/ckfw/builtins/nssckbi.h",
-      "nss/lib/ckfw/ck.h",
-      "nss/lib/ckfw/ckfw.h",
-      "nss/lib/ckfw/ckfwm.h",
-      "nss/lib/ckfw/ckfwtm.h",
-      "nss/lib/ckfw/ckmd.h",
-      "nss/lib/ckfw/ckt.h",
-      "nss/lib/ckfw/crypto.c",
-      "nss/lib/ckfw/find.c",
-      "nss/lib/ckfw/hash.c",
-      "nss/lib/ckfw/instance.c",
-      "nss/lib/ckfw/mechanism.c",
-      "nss/lib/ckfw/mutex.c",
-      "nss/lib/ckfw/nssck.api",
-      "nss/lib/ckfw/nssckepv.h",
-      "nss/lib/ckfw/nssckft.h",
-      "nss/lib/ckfw/nssckfw.h",
-      "nss/lib/ckfw/nssckfwc.h",
-      "nss/lib/ckfw/nssckfwt.h",
-      "nss/lib/ckfw/nssckg.h",
-      "nss/lib/ckfw/nssckmdt.h",
-      "nss/lib/ckfw/nssckt.h",
-      "nss/lib/ckfw/object.c",
-      "nss/lib/ckfw/session.c",
-      "nss/lib/ckfw/sessobj.c",
-      "nss/lib/ckfw/slot.c",
-      "nss/lib/ckfw/token.c",
-      "nss/lib/ckfw/wrap.c",
-    ]
-
-    configs -= [ "//build/config/compiler:chromium_code" ]
-
-    if (is_win) {
-      configs -= [ "//build/config/win:unicode" ]  # Requires 8-bit mode.
-    }
-    configs += [ "//build/config/compiler:no_chromium_code" ]
-
-    include_dirs = [ "nss/lib/ckfw" ]
-    public_configs = [ ":nssckbi_config" ]
-
-    public_deps = [
-      ":nss_static",
-    ]
-  }
-
-  config("nss_static_config") {
-    defines = [
-      "NSS_STATIC",
-      "NSS_USE_STATIC_LIBS",
-      "USE_UTIL_DIRECTLY",
-    ]
-    if (is_win) {
-      defines += [ "_WINDOWS" ]
-    }
-    include_dirs = [
-      "nspr/pr/include",
-      "nspr/lib/ds",
-      "nspr/lib/libc/include",
-      "nss/lib/base",
-      "nss/lib/certdb",
-      "nss/lib/certhigh",
-      "nss/lib/cryptohi",
-      "nss/lib/dev",
-      "nss/lib/freebl",
-      "nss/lib/freebl/ecl",
-      "nss/lib/nss",
-      "nss/lib/pk11wrap",
-      "nss/lib/pkcs7",
-      "nss/lib/pki",
-      "nss/lib/smime",
-      "nss/lib/softoken",
-      "nss/lib/util",
-    ]
-  }
-
-  if (is_win && current_cpu == "x86") {
-    source_set("nss_static_avx") {
-      sources = [
-        "nss/lib/freebl/intel-gcm-wrap.c",
-        "nss/lib/freebl/intel-gcm-x86-masm.asm",
-        "nss/lib/freebl/intel-gcm.h",
-      ]
-      defines = [
-        "_WINDOWS",
-        "_X86_",
-        "INTEL_GCM",
-        "MP_API_COMPATIBLE",
-        "MP_ASSEMBLY_DIV_2DX1D",
-        "MP_ASSEMBLY_MULTIPLY",
-        "MP_ASSEMBLY_SQUARE",
-        "MP_NO_MP_WORD",
-        "MP_USE_UINT_DIGIT",
-        "NSS_DISABLE_DBM",
-        "NSS_STATIC",
-        "NSS_USE_STATIC_LIBS",
-        "NSS_X86",
-        "NSS_X86_OR_X64",
-        "RIJNDAEL_INCLUDE_TABLES",
-        "SHLIB_PREFIX=\"\"",
-        "SHLIB_SUFFIX=\"dll\"",
-        "SHLIB_VERSION=\"3\"",
-        "SOFTOKEN_LIB_NAME=\"softokn3.dll\"",
-        "SOFTOKEN_SHLIB_VERSION=\"3\"",
-        "USE_HW_AES",
-        "USE_UTIL_DIRECTLY",
-        "WIN32",
-        "WIN95",
-        "XP_PC",
-      ]
-      include_dirs = [
-        "nspr/pr/include",
-        "nspr/lib/ds",
-        "nspr/lib/libc/include",
-        "nss/lib/freebl/ecl",
-        "nss/lib/util",
-      ]
-    }
-  }
-
-  source_set("nss_static") {
-    visibility = [ ":*" ]  # Internal implementation detail.
-
-    sources = [
-      "nss/lib/base/arena.c",
-      "nss/lib/base/base.h",
-      "nss/lib/base/baset.h",
-      "nss/lib/base/error.c",
-      "nss/lib/base/errorval.c",
-      "nss/lib/base/hash.c",
-      "nss/lib/base/hashops.c",
-      "nss/lib/base/item.c",
-      "nss/lib/base/libc.c",
-      "nss/lib/base/list.c",
-      "nss/lib/base/nssbase.h",
-      "nss/lib/base/nssbaset.h",
-      "nss/lib/base/nssutf8.c",
-      "nss/lib/base/tracker.c",
-      "nss/lib/certdb/alg1485.c",
-      "nss/lib/certdb/cert.h",
-      "nss/lib/certdb/certdb.c",
-      "nss/lib/certdb/certdb.h",
-      "nss/lib/certdb/certi.h",
-      "nss/lib/certdb/certt.h",
-      "nss/lib/certdb/certv3.c",
-      "nss/lib/certdb/certxutl.c",
-      "nss/lib/certdb/certxutl.h",
-      "nss/lib/certdb/crl.c",
-      "nss/lib/certdb/genname.c",
-      "nss/lib/certdb/genname.h",
-      "nss/lib/certdb/polcyxtn.c",
-      "nss/lib/certdb/secname.c",
-      "nss/lib/certdb/stanpcertdb.c",
-      "nss/lib/certdb/xauthkid.c",
-      "nss/lib/certdb/xbsconst.c",
-      "nss/lib/certdb/xconst.c",
-      "nss/lib/certdb/xconst.h",
-      "nss/lib/certhigh/certhigh.c",
-      "nss/lib/certhigh/certhtml.c",
-      "nss/lib/certhigh/certreq.c",
-      "nss/lib/certhigh/certvfy.c",
-      "nss/lib/certhigh/crlv2.c",
-      "nss/lib/certhigh/ocsp.c",
-      "nss/lib/certhigh/ocsp.h",
-      "nss/lib/certhigh/ocspi.h",
-      "nss/lib/certhigh/ocspsig.c",
-      "nss/lib/certhigh/ocspt.h",
-      "nss/lib/certhigh/ocspti.h",
-      "nss/lib/certhigh/xcrldist.c",
-      "nss/lib/cryptohi/cryptohi.h",
-      "nss/lib/cryptohi/cryptoht.h",
-      "nss/lib/cryptohi/dsautil.c",
-      "nss/lib/cryptohi/key.h",
-      "nss/lib/cryptohi/keyhi.h",
-      "nss/lib/cryptohi/keyi.h",
-      "nss/lib/cryptohi/keyt.h",
-      "nss/lib/cryptohi/keythi.h",
-      "nss/lib/cryptohi/sechash.c",
-      "nss/lib/cryptohi/sechash.h",
-      "nss/lib/cryptohi/seckey.c",
-      "nss/lib/cryptohi/secsign.c",
-      "nss/lib/cryptohi/secvfy.c",
-      "nss/lib/dev/ckhelper.c",
-      "nss/lib/dev/ckhelper.h",
-      "nss/lib/dev/dev.h",
-      "nss/lib/dev/devm.h",
-      "nss/lib/dev/devslot.c",
-      "nss/lib/dev/devt.h",
-      "nss/lib/dev/devtm.h",
-      "nss/lib/dev/devtoken.c",
-      "nss/lib/dev/devutil.c",
-      "nss/lib/dev/nssdev.h",
-      "nss/lib/dev/nssdevt.h",
-      "nss/lib/freebl/aeskeywrap.c",
-      "nss/lib/freebl/alg2268.c",
-      "nss/lib/freebl/alghmac.c",
-      "nss/lib/freebl/alghmac.h",
-      "nss/lib/freebl/arcfive.c",
-      "nss/lib/freebl/arcfour.c",
-      "nss/lib/freebl/blapi.h",
-      "nss/lib/freebl/blapii.h",
-      "nss/lib/freebl/blapit.h",
-      "nss/lib/freebl/camellia.c",
-      "nss/lib/freebl/camellia.h",
-      "nss/lib/freebl/chacha20/chacha20.c",
-      "nss/lib/freebl/chacha20/chacha20.h",
-      "nss/lib/freebl/chacha20/chacha20_vec.c",
-      "nss/lib/freebl/chacha20poly1305.c",
-      "nss/lib/freebl/chacha20poly1305.h",
-      "nss/lib/freebl/ctr.c",
-      "nss/lib/freebl/ctr.h",
-      "nss/lib/freebl/cts.c",
-      "nss/lib/freebl/cts.h",
-      "nss/lib/freebl/des.c",
-      "nss/lib/freebl/des.h",
-      "nss/lib/freebl/desblapi.c",
-      "nss/lib/freebl/dh.c",
-      "nss/lib/freebl/drbg.c",
-      "nss/lib/freebl/dsa.c",
-      "nss/lib/freebl/ec.c",
-      "nss/lib/freebl/ec.h",
-      "nss/lib/freebl/ecdecode.c",
-      "nss/lib/freebl/ecl/ec2.h",
-      "nss/lib/freebl/ecl/ec_naf.c",
-      "nss/lib/freebl/ecl/ecl-curve.h",
-      "nss/lib/freebl/ecl/ecl-exp.h",
-      "nss/lib/freebl/ecl/ecl-priv.h",
-      "nss/lib/freebl/ecl/ecl.c",
-      "nss/lib/freebl/ecl/ecl.h",
-      "nss/lib/freebl/ecl/ecl_curve.c",
-      "nss/lib/freebl/ecl/ecl_gf.c",
-      "nss/lib/freebl/ecl/ecl_mult.c",
-      "nss/lib/freebl/ecl/ecp.h",
-      "nss/lib/freebl/ecl/ecp_256.c",
-      "nss/lib/freebl/ecl/ecp_256_32.c",
-      "nss/lib/freebl/ecl/ecp_384.c",
-      "nss/lib/freebl/ecl/ecp_521.c",
-      "nss/lib/freebl/ecl/ecp_aff.c",
-      "nss/lib/freebl/ecl/ecp_jac.c",
-      "nss/lib/freebl/ecl/ecp_jm.c",
-      "nss/lib/freebl/ecl/ecp_mont.c",
-      "nss/lib/freebl/gcm.c",
-      "nss/lib/freebl/gcm.h",
-      "nss/lib/freebl/hmacct.c",
-      "nss/lib/freebl/hmacct.h",
-      "nss/lib/freebl/intel-aes-x86-masm.asm",
-      "nss/lib/freebl/intel-aes.h",
-      "nss/lib/freebl/jpake.c",
-      "nss/lib/freebl/md2.c",
-      "nss/lib/freebl/md5.c",
-      "nss/lib/freebl/mpi/logtab.h",
-      "nss/lib/freebl/mpi/mp_gf2m-priv.h",
-      "nss/lib/freebl/mpi/mp_gf2m.c",
-      "nss/lib/freebl/mpi/mp_gf2m.h",
-      "nss/lib/freebl/mpi/mpcpucache.c",
-      "nss/lib/freebl/mpi/mpi-config.h",
-      "nss/lib/freebl/mpi/mpi-priv.h",
-      "nss/lib/freebl/mpi/mpi.c",
-      "nss/lib/freebl/mpi/mpi.h",
-      "nss/lib/freebl/mpi/mpi_amd64.c",
-      "nss/lib/freebl/mpi/mpi_arm.c",
-      "nss/lib/freebl/mpi/mpi_arm_mac.c",
-      "nss/lib/freebl/mpi/mpi_x86_asm.c",
-      "nss/lib/freebl/mpi/mplogic.c",
-      "nss/lib/freebl/mpi/mplogic.h",
-      "nss/lib/freebl/mpi/mpmontg.c",
-      "nss/lib/freebl/mpi/mpprime.c",
-      "nss/lib/freebl/mpi/mpprime.h",
-      "nss/lib/freebl/mpi/primes.c",
-      "nss/lib/freebl/nss_build_config_mac.h",
-      "nss/lib/freebl/poly1305/poly1305-donna-x64-sse2-incremental-source.c",
-      "nss/lib/freebl/poly1305/poly1305.c",
-      "nss/lib/freebl/poly1305/poly1305.h",
-      "nss/lib/freebl/pqg.c",
-      "nss/lib/freebl/pqg.h",
-      "nss/lib/freebl/rawhash.c",
-      "nss/lib/freebl/rijndael.c",
-      "nss/lib/freebl/rijndael.h",
-      "nss/lib/freebl/rijndael32.tab",
-      "nss/lib/freebl/rsa.c",
-      "nss/lib/freebl/rsapkcs.c",
-      "nss/lib/freebl/secmpi.h",
-      "nss/lib/freebl/secrng.h",
-      "nss/lib/freebl/seed.c",
-      "nss/lib/freebl/seed.h",
-      "nss/lib/freebl/sha256.h",
-      "nss/lib/freebl/sha512.c",
-      "nss/lib/freebl/sha_fast.c",
-      "nss/lib/freebl/sha_fast.h",
-      "nss/lib/freebl/shsign.h",
-      "nss/lib/freebl/shvfy.c",
-      "nss/lib/freebl/sysrand.c",
-      "nss/lib/freebl/tlsprfalg.c",
-      "nss/lib/freebl/unix_rand.c",
-      "nss/lib/freebl/win_rand.c",
-      "nss/lib/nss/nss.h",
-      "nss/lib/nss/nssinit.c",
-      "nss/lib/nss/nssrenam.h",
-      "nss/lib/nss/utilwrap.c",
-      "nss/lib/pk11wrap/debug_module.c",
-      "nss/lib/pk11wrap/dev3hack.c",
-      "nss/lib/pk11wrap/dev3hack.h",
-      "nss/lib/pk11wrap/pk11akey.c",
-      "nss/lib/pk11wrap/pk11auth.c",
-      "nss/lib/pk11wrap/pk11cert.c",
-      "nss/lib/pk11wrap/pk11cxt.c",
-      "nss/lib/pk11wrap/pk11err.c",
-      "nss/lib/pk11wrap/pk11func.h",
-      "nss/lib/pk11wrap/pk11kea.c",
-      "nss/lib/pk11wrap/pk11list.c",
-      "nss/lib/pk11wrap/pk11load.c",
-      "nss/lib/pk11wrap/pk11mech.c",
-      "nss/lib/pk11wrap/pk11merge.c",
-      "nss/lib/pk11wrap/pk11nobj.c",
-      "nss/lib/pk11wrap/pk11obj.c",
-      "nss/lib/pk11wrap/pk11pars.c",
-      "nss/lib/pk11wrap/pk11pbe.c",
-      "nss/lib/pk11wrap/pk11pk12.c",
-      "nss/lib/pk11wrap/pk11pqg.c",
-      "nss/lib/pk11wrap/pk11pqg.h",
-      "nss/lib/pk11wrap/pk11priv.h",
-      "nss/lib/pk11wrap/pk11pub.h",
-      "nss/lib/pk11wrap/pk11sdr.c",
-      "nss/lib/pk11wrap/pk11sdr.h",
-      "nss/lib/pk11wrap/pk11skey.c",
-      "nss/lib/pk11wrap/pk11slot.c",
-      "nss/lib/pk11wrap/pk11util.c",
-      "nss/lib/pk11wrap/secmod.h",
-      "nss/lib/pk11wrap/secmodi.h",
-      "nss/lib/pk11wrap/secmodt.h",
-      "nss/lib/pk11wrap/secmodti.h",
-      "nss/lib/pk11wrap/secpkcs5.h",
-      "nss/lib/pkcs7/certread.c",
-      "nss/lib/pkcs7/p7common.c",
-      "nss/lib/pkcs7/p7create.c",
-      "nss/lib/pkcs7/p7decode.c",
-      "nss/lib/pkcs7/p7encode.c",
-      "nss/lib/pkcs7/p7local.c",
-      "nss/lib/pkcs7/p7local.h",
-      "nss/lib/pkcs7/pkcs7t.h",
-      "nss/lib/pkcs7/secmime.c",
-      "nss/lib/pkcs7/secmime.h",
-      "nss/lib/pkcs7/secpkcs7.h",
-      "nss/lib/pki/asymmkey.c",
-      "nss/lib/pki/certdecode.c",
-      "nss/lib/pki/certificate.c",
-      "nss/lib/pki/cryptocontext.c",
-      "nss/lib/pki/nsspki.h",
-      "nss/lib/pki/nsspkit.h",
-      "nss/lib/pki/pki.h",
-      "nss/lib/pki/pki3hack.c",
-      "nss/lib/pki/pki3hack.h",
-      "nss/lib/pki/pkibase.c",
-      "nss/lib/pki/pkim.h",
-      "nss/lib/pki/pkistore.c",
-      "nss/lib/pki/pkistore.h",
-      "nss/lib/pki/pkit.h",
-      "nss/lib/pki/pkitm.h",
-      "nss/lib/pki/symmkey.c",
-      "nss/lib/pki/tdcache.c",
-      "nss/lib/pki/trustdomain.c",
-      "nss/lib/smime/cms.h",
-      "nss/lib/smime/cmslocal.h",
-      "nss/lib/smime/cmsreclist.h",
-      "nss/lib/smime/cmst.h",
-      "nss/lib/smime/smime.h",
-      "nss/lib/softoken/fipsaudt.c",
-      "nss/lib/softoken/fipstest.c",
-      "nss/lib/softoken/fipstokn.c",
-      "nss/lib/softoken/jpakesftk.c",
-      "nss/lib/softoken/lgglue.c",
-      "nss/lib/softoken/lgglue.h",
-      "nss/lib/softoken/lowkey.c",
-      "nss/lib/softoken/lowkeyi.h",
-      "nss/lib/softoken/lowkeyti.h",
-      "nss/lib/softoken/lowpbe.c",
-      "nss/lib/softoken/lowpbe.h",
-      "nss/lib/softoken/padbuf.c",
-      "nss/lib/softoken/pkcs11.c",
-      "nss/lib/softoken/pkcs11c.c",
-      "nss/lib/softoken/pkcs11i.h",
-      "nss/lib/softoken/pkcs11ni.h",
-      "nss/lib/softoken/pkcs11u.c",
-      "nss/lib/softoken/sdb.c",
-      "nss/lib/softoken/sdb.h",
-      "nss/lib/softoken/sftkdb.c",
-      "nss/lib/softoken/sftkdb.h",
-      "nss/lib/softoken/sftkdbt.h",
-      "nss/lib/softoken/sftkdbti.h",
-      "nss/lib/softoken/sftkhmac.c",
-      "nss/lib/softoken/sftkpars.c",
-      "nss/lib/softoken/sftkpars.h",
-      "nss/lib/softoken/sftkpwd.c",
-      "nss/lib/softoken/softkver.c",
-      "nss/lib/softoken/softkver.h",
-      "nss/lib/softoken/softoken.h",
-      "nss/lib/softoken/softoknt.h",
-      "nss/lib/softoken/tlsprf.c",
-      "nss/lib/ssl/sslerr.h",
-      "nss/lib/util/SECerrs.h",
-      "nss/lib/util/base64.h",
-      "nss/lib/util/ciferfam.h",
-      "nss/lib/util/derdec.c",
-      "nss/lib/util/derenc.c",
-      "nss/lib/util/dersubr.c",
-      "nss/lib/util/dertime.c",
-      "nss/lib/util/errstrs.c",
-      "nss/lib/util/hasht.h",
-      "nss/lib/util/nssb64.h",
-      "nss/lib/util/nssb64d.c",
-      "nss/lib/util/nssb64e.c",
-      "nss/lib/util/nssb64t.h",
-      "nss/lib/util/nssilckt.h",
-      "nss/lib/util/nssilock.c",
-      "nss/lib/util/nssilock.h",
-      "nss/lib/util/nsslocks.h",
-      "nss/lib/util/nssrwlk.c",
-      "nss/lib/util/nssrwlk.h",
-      "nss/lib/util/nssrwlkt.h",
-      "nss/lib/util/nssutil.h",
-      "nss/lib/util/oidstring.c",
-      "nss/lib/util/pkcs11.h",
-      "nss/lib/util/pkcs11f.h",
-      "nss/lib/util/pkcs11n.h",
-      "nss/lib/util/pkcs11p.h",
-      "nss/lib/util/pkcs11t.h",
-      "nss/lib/util/pkcs11u.h",
-      "nss/lib/util/pkcs1sig.c",
-      "nss/lib/util/pkcs1sig.h",
-      "nss/lib/util/portreg.c",
-      "nss/lib/util/portreg.h",
-      "nss/lib/util/quickder.c",
-      "nss/lib/util/secalgid.c",
-      "nss/lib/util/secasn1.h",
-      "nss/lib/util/secasn1d.c",
-      "nss/lib/util/secasn1e.c",
-      "nss/lib/util/secasn1t.h",
-      "nss/lib/util/secasn1u.c",
-      "nss/lib/util/seccomon.h",
-      "nss/lib/util/secder.h",
-      "nss/lib/util/secdert.h",
-      "nss/lib/util/secdig.c",
-      "nss/lib/util/secdig.h",
-      "nss/lib/util/secdigt.h",
-      "nss/lib/util/secerr.h",
-      "nss/lib/util/secitem.c",
-      "nss/lib/util/secitem.h",
-      "nss/lib/util/secoid.c",
-      "nss/lib/util/secoid.h",
-      "nss/lib/util/secoidt.h",
-      "nss/lib/util/secport.c",
-      "nss/lib/util/secport.h",
-      "nss/lib/util/sectime.c",
-      "nss/lib/util/templates.c",
-      "nss/lib/util/utf8.c",
-      "nss/lib/util/utilmod.c",
-      "nss/lib/util/utilmodt.h",
-      "nss/lib/util/utilpars.c",
-      "nss/lib/util/utilpars.h",
-      "nss/lib/util/utilparst.h",
-      "nss/lib/util/utilrename.h",
-    ]
-
-    sources -= [
-      # mpi_arm.c is included by mpi_arm_mac.c.
-      # NOTE: mpi_arm.c can be used directly on Linux. mpi_arm.c will need
-      # to be excluded conditionally if we start to build NSS on Linux.
-      "nss/lib/freebl/mpi/mpi_arm.c",
-
-      # primes.c is included by mpprime.c.
-      "nss/lib/freebl/mpi/primes.c",
-
-      # unix_rand.c and win_rand.c are included by sysrand.c.
-      "nss/lib/freebl/unix_rand.c",
-      "nss/lib/freebl/win_rand.c",
-
-      # debug_module.c is included by pk11load.c.
-      "nss/lib/pk11wrap/debug_module.c",
-    ]
-
-    configs -= [ "//build/config/compiler:chromium_code" ]
-    if (is_win) {
-      configs -= [ "//build/config/win:unicode" ]  # Requires 8-bit mode.
-    }
-    configs += [
-      "//build/config/compiler:no_chromium_code",
-      "//build/config/compiler:no_size_t_to_int_warning",
-    ]
-    public_configs = [ ":nss_static_config" ]
-
-    cflags = []
-
-    # Only need the defines and includes not in nss_static_config.
-    defines = [
-      "MP_API_COMPATIBLE",
-      "NSS_DISABLE_DBM",
-      "RIJNDAEL_INCLUDE_TABLES",
-      "SHLIB_VERSION=\"3\"",
-      "SOFTOKEN_SHLIB_VERSION=\"3\"",
-    ]
-    include_dirs = [
-      "nss/lib/freebl/mpi",
-      "nss/lib/ssl",
-    ]
-
-    if (is_win) {
-      cflags += [ "/wd4101" ]  # Unreferenced local variable.
-    }
-
-    if (include_nss_libpkix) {
-      sources += [
-        "nss/lib/certhigh/certvfypkix.c",
-        "nss/lib/certhigh/certvfypkixprint.c",
-        "nss/lib/libpkix/include/pkix.h",
-        "nss/lib/libpkix/include/pkix_certsel.h",
-        "nss/lib/libpkix/include/pkix_certstore.h",
-        "nss/lib/libpkix/include/pkix_checker.h",
-        "nss/lib/libpkix/include/pkix_crlsel.h",
-        "nss/lib/libpkix/include/pkix_errorstrings.h",
-        "nss/lib/libpkix/include/pkix_params.h",
-        "nss/lib/libpkix/include/pkix_pl_pki.h",
-        "nss/lib/libpkix/include/pkix_pl_system.h",
-        "nss/lib/libpkix/include/pkix_results.h",
-        "nss/lib/libpkix/include/pkix_revchecker.h",
-        "nss/lib/libpkix/include/pkix_sample_modules.h",
-        "nss/lib/libpkix/include/pkix_util.h",
-        "nss/lib/libpkix/include/pkixt.h",
-        "nss/lib/libpkix/pkix/certsel/pkix_certselector.c",
-        "nss/lib/libpkix/pkix/certsel/pkix_certselector.h",
-        "nss/lib/libpkix/pkix/certsel/pkix_comcertselparams.c",
-        "nss/lib/libpkix/pkix/certsel/pkix_comcertselparams.h",
-        "nss/lib/libpkix/pkix/checker/pkix_basicconstraintschecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_basicconstraintschecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_certchainchecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_certchainchecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_crlchecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_crlchecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_ekuchecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_ekuchecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_expirationchecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_expirationchecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_namechainingchecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_namechainingchecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_nameconstraintschecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_nameconstraintschecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_ocspchecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_ocspchecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_policychecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_policychecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_revocationchecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_revocationchecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_revocationmethod.c",
-        "nss/lib/libpkix/pkix/checker/pkix_revocationmethod.h",
-        "nss/lib/libpkix/pkix/checker/pkix_signaturechecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_signaturechecker.h",
-        "nss/lib/libpkix/pkix/checker/pkix_targetcertchecker.c",
-        "nss/lib/libpkix/pkix/checker/pkix_targetcertchecker.h",
-        "nss/lib/libpkix/pkix/crlsel/pkix_comcrlselparams.c",
-        "nss/lib/libpkix/pkix/crlsel/pkix_comcrlselparams.h",
-        "nss/lib/libpkix/pkix/crlsel/pkix_crlselector.c",
-        "nss/lib/libpkix/pkix/crlsel/pkix_crlselector.h",
-        "nss/lib/libpkix/pkix/params/pkix_procparams.c",
-        "nss/lib/libpkix/pkix/params/pkix_procparams.h",
-        "nss/lib/libpkix/pkix/params/pkix_resourcelimits.c",
-        "nss/lib/libpkix/pkix/params/pkix_resourcelimits.h",
-        "nss/lib/libpkix/pkix/params/pkix_trustanchor.c",
-        "nss/lib/libpkix/pkix/params/pkix_trustanchor.h",
-        "nss/lib/libpkix/pkix/params/pkix_valparams.c",
-        "nss/lib/libpkix/pkix/params/pkix_valparams.h",
-        "nss/lib/libpkix/pkix/results/pkix_buildresult.c",
-        "nss/lib/libpkix/pkix/results/pkix_buildresult.h",
-        "nss/lib/libpkix/pkix/results/pkix_policynode.c",
-        "nss/lib/libpkix/pkix/results/pkix_policynode.h",
-        "nss/lib/libpkix/pkix/results/pkix_valresult.c",
-        "nss/lib/libpkix/pkix/results/pkix_valresult.h",
-        "nss/lib/libpkix/pkix/results/pkix_verifynode.c",
-        "nss/lib/libpkix/pkix/results/pkix_verifynode.h",
-        "nss/lib/libpkix/pkix/store/pkix_store.c",
-        "nss/lib/libpkix/pkix/store/pkix_store.h",
-        "nss/lib/libpkix/pkix/top/pkix_build.c",
-        "nss/lib/libpkix/pkix/top/pkix_build.h",
-        "nss/lib/libpkix/pkix/top/pkix_lifecycle.c",
-        "nss/lib/libpkix/pkix/top/pkix_lifecycle.h",
-        "nss/lib/libpkix/pkix/top/pkix_validate.c",
-        "nss/lib/libpkix/pkix/top/pkix_validate.h",
-        "nss/lib/libpkix/pkix/util/pkix_error.c",
-        "nss/lib/libpkix/pkix/util/pkix_error.h",
-        "nss/lib/libpkix/pkix/util/pkix_errpaths.c",
-        "nss/lib/libpkix/pkix/util/pkix_list.c",
-        "nss/lib/libpkix/pkix/util/pkix_list.h",
-        "nss/lib/libpkix/pkix/util/pkix_logger.c",
-        "nss/lib/libpkix/pkix/util/pkix_logger.h",
-        "nss/lib/libpkix/pkix/util/pkix_tools.c",
-        "nss/lib/libpkix/pkix/util/pkix_tools.h",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_aiamgr.c",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_aiamgr.h",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_colcertstore.c",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_colcertstore.h",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_httpcertstore.c",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_httpcertstore.h",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_httpdefaultclient.c",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_httpdefaultclient.h",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_nsscontext.c",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_nsscontext.h",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_pk11certstore.c",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_pk11certstore.h",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_socket.c",
-        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_socket.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_basicconstraints.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_basicconstraints.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_cert.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_cert.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicyinfo.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicyinfo.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicymap.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicymap.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicyqualifier.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicyqualifier.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crl.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crl.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crldp.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crldp.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crlentry.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crlentry.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_date.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_date.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_generalname.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_generalname.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_infoaccess.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_infoaccess.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_nameconstraints.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_nameconstraints.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocspcertid.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocspcertid.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocsprequest.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocsprequest.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocspresponse.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocspresponse.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_publickey.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_publickey.h",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_x500name.c",
-        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_x500name.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_bigint.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_bigint.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_bytearray.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_bytearray.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_common.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_common.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_error.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_hashtable.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_hashtable.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_lifecycle.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_lifecycle.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_mem.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_mem.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_monitorlock.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_monitorlock.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_mutex.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_mutex.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_object.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_object.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_oid.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_oid.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_primhash.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_primhash.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.h",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_string.c",
-        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_string.h",
-      ]
-
-      # Disable the LDAP code in libpkix.
-      defines += [ "NSS_PKIX_NO_LDAP" ]
-
-      include_dirs += [
-        "nss/lib/libpkix/include",
-        "nss/lib/libpkix/pkix/certsel",
-        "nss/lib/libpkix/pkix/checker",
-        "nss/lib/libpkix/pkix/crlsel",
-        "nss/lib/libpkix/pkix/params",
-        "nss/lib/libpkix/pkix/results",
-        "nss/lib/libpkix/pkix/store",
-        "nss/lib/libpkix/pkix/top",
-        "nss/lib/libpkix/pkix/util",
-        "nss/lib/libpkix/pkix_pl_nss/module",
-        "nss/lib/libpkix/pkix_pl_nss/pki",
-        "nss/lib/libpkix/pkix_pl_nss/system",
-      ]
-    } else {
-      defines += [ "NSS_DISABLE_LIBPKIX" ]
-    }
-
-    if (!include_nss_root_certs) {
-      defines += [ "NSS_DISABLE_ROOT_CERTS" ]
-    }
-
-    if (current_cpu == "x64" && !is_win) {
-      sources -= [
-        "nss/lib/freebl/chacha20/chacha20.c",
-        "nss/lib/freebl/poly1305/poly1305.c",
-      ]
-    } else {
-      sources -= [
-        "nss/lib/freebl/chacha20/chacha20_vec.c",
-        "nss/lib/freebl/poly1305/poly1305-donna-x64-sse2-incremental-source.c",
-      ]
-    }
-
-    if (is_mac || is_ios) {
-      sources -= [ "nss/lib/freebl/mpi/mpi_amd64.c" ]
-      cflags += [
-        "-include",
-        rebase_path("//third_party/nss/nss/lib/freebl/nss_build_config_mac.h",
-                    root_build_dir),
-      ]
-      defines += [
-        "XP_UNIX",
-        "DARWIN",
-        "HAVE_STRERROR",
-        "HAVE_BSD_FLOCK",
-        "SHLIB_SUFFIX=\"dylib\"",
-        "SHLIB_PREFIX=\"lib\"",
-        "SOFTOKEN_LIB_NAME=\"libsoftokn3.dylib\"",
-      ]
-
-      configs -= [ "//build/config/gcc:symbol_visibility_hidden" ]
-    } else {
-      # Not Mac/iOS.
-      sources -= [ "nss/lib/freebl/mpi/mpi_arm_mac.c" ]
-    }
-
-    if (is_win) {
-      defines += [
-        "SHLIB_SUFFIX=\"dll\"",
-        "SHLIB_PREFIX=\"\"",
-        "SOFTOKEN_LIB_NAME=\"softokn3.dll\"",
-        "XP_PC",
-        "WIN32",
-        "WIN95",
-      ]
-
-      if (current_cpu == "x86") {
-        defines += [
-          "NSS_X86_OR_X64",
-          "NSS_X86",
-          "_X86_",
-          "MP_ASSEMBLY_MULTIPLY",
-          "MP_ASSEMBLY_SQUARE",
-          "MP_ASSEMBLY_DIV_2DX1D",
-          "MP_USE_UINT_DIGIT",
-          "MP_NO_MP_WORD",
-          "USE_HW_AES",
-          "INTEL_GCM",
-        ]
-        sources -= [ "nss/lib/freebl/mpi/mpi_amd64.c" ]
-      } else if (current_cpu == "x64") {
-        sources -= [
-          "nss/lib/freebl/intel-aes-x86-masm.asm",
-          "nss/lib/freebl/mpi/mpi_amd64.c",
-          "nss/lib/freebl/mpi/mpi_x86_asm.c",
-        ]
-        defines += [
-          "NSS_USE_64",
-          "NSS_X86_OR_X64",
-          "NSS_X64",
-          "_AMD64_",
-          "MP_CHAR_STORE_SLOW",
-          "MP_IS_LITTLE_ENDIAN",
-          "WIN64",
-        ]
-      }
-    } else {
-      # Not Windows.
-      sources -= [
-        # mpi_x86_asm.c contains MSVC inline assembly code.
-        "nss/lib/freebl/mpi/mpi_x86_asm.c",
-      ]
-    }
-
-    if (is_clang) {
-      cflags += [
-        # nss doesn"t explicitly cast between different enum types.
-        "-Wno-conversion",
-
-        # nss passes "const char*" through "void*".
-        "-Wno-incompatible-pointer-types",
-
-        # nss prefers `a && b || c` over `(a && b) || c`.
-        "-Wno-logical-op-parentheses",
-
-        # nss doesn"t use exhaustive switches on enums
-        "-Wno-switch",
-
-        # nss has some `unsigned < 0` checks.
-        "-Wno-tautological-compare",
-      ]
-    }
-
-    public_deps = [
-      ":nspr",
-    ]
-    deps = [
-      ":nspr",
-      "//third_party/sqlite",
-    ]
-
-    if (is_win && current_cpu == "x86") {
-      deps += [ ":nss_static_avx" ]
-    }
-  }
-}  # Windows/Mac/iOS.
diff --git a/build/secondary/tools/grit/BUILD.gn b/build/secondary/tools/grit/BUILD.gn
deleted file mode 100644
index 660bf1b1ebc..00000000000
--- a/build/secondary/tools/grit/BUILD.gn
+++ /dev/null
@@ -1,27 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This target creates a stamp file that depends on all the sources in the grit
-# directory. By depending on this, a target can force itself to be rebuilt if
-# grit itself changes.
-action("grit_sources") {
-  depfile = "$target_out_dir/grit_sources.d"
-  script = "//build/secondary/tools/grit/stamp_grit_sources.py"
-
-  inputs = [
-    "grit.py",
-  ]
-
-  # Note that we can't call this "grit_sources.stamp" because that file is
-  # implicitly created by GN for script actions.
-  outputs = [
-    "$target_out_dir/grit_sources.script.stamp",
-  ]
-
-  args = [
-    rebase_path("//tools/grit", root_build_dir),
-    rebase_path(outputs[0], root_build_dir),
-    rebase_path(depfile, root_build_dir),
-  ]
-}
diff --git a/build/secondary/tools/grit/grit_rule.gni b/build/secondary/tools/grit/grit_rule.gni
deleted file mode 100644
index bdf812f219d..00000000000
--- a/build/secondary/tools/grit/grit_rule.gni
+++ /dev/null
@@ -1,483 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Instantiate grit. This will produce a script target to run grit, and a
-# static library that compiles the .cc files.
-#
-# Parameters
-#
-#   source (required)
-#       Path to .grd file.
-#
-#   outputs (required)
-#       List of outputs from grit, relative to the target_gen_dir. Grit will
-#       verify at build time that this list is correct and will fail if there
-#       is a mismatch between the outputs specified by the .grd file and the
-#       outputs list here.
-#
-#       To get this list, you can look in the .grd file for
-#       <output filename="..." and put those filename here. The base directory
-#       of the list in Grit and the output list specified in the GN grit target
-#       are the same (the target_gen_dir) so you can generally copy the names
-#       exactly.
-#
-#       To get the list of outputs programatically, run:
-#           python tools/grit/grit_info.py --outputs . path/to/your.grd
-#       And strip the leading "./" from the output files.
-#
-#   defines (optional)
-#       Extra defines to pass to grit (on top of the global grit_defines list).
-#
-#   grit_flags (optional)
-#       List of strings containing extra command-line flags to pass to Grit.
-#
-#   resource_ids (optional)
-#       Path to a grit "firstidsfile". Default is
-#       //tools/gritsettings/resource_ids. Set to "" to use the value specified
-#       in the <grit> nodes of the processed files.
-#
-#   output_dir (optional)
-#       Directory for generated files. If you specify this, you will often
-#       want to specify output_name if the target name is not particularly
-#       unique, since this can cause files from multiple grit targets to
-#       overwrite each other.
-#
-#   output_name (optiona)
-#       Provide an alternate base name for the generated files, like the .d
-#       files. Normally these are based on the target name and go in the
-#       output_dir, but if multiple targets with the same name end up in
-#       the same output_dir, they can collide.
-#
-#   depfile_dir (optional)
-#       If set, used to store the depfile and corresponding stamp file.
-#       Defaults to output_dir
-#
-#   use_qualified_include (optional)
-#       If set, output_dir is not added to include_dirs.
-#
-#   configs (optional)
-#       List of additional configs to be applied to the generated target.
-#   deps  (optional)
-#   inputs  (optional)
-#       List of additional files, required for grit to process source file.
-#   visibility  (optional)
-#       Normal meaning.
-#
-# Example
-#
-#   grit("my_resources") {
-#     # Source and outputs are required.
-#     source = "myfile.grd"
-#     outputs = [
-#       "foo_strings.h",
-#       "foo_strings.pak",
-#     ]
-#
-#     grit_flags = [ "-E", "foo=bar" ]  # Optional extra flags.
-#     # You can also put deps here if the grit source depends on generated
-#     # files.
-#   }
-import("//build/config/chrome_build.gni")
-import("//build/config/crypto.gni")
-import("//build/config/features.gni")
-import("//build/config/ui.gni")
-
-grit_defines = []
-
-# Mac and iOS want Title Case strings.
-use_titlecase_in_grd_files = is_mac || is_ios
-if (use_titlecase_in_grd_files) {
-  grit_defines += [
-    "-D",
-    "use_titlecase",
-  ]
-}
-
-if (is_chrome_branded) {
-  grit_defines += [
-    "-D",
-    "_google_chrome",
-    "-E",
-    "CHROMIUM_BUILD=google_chrome",
-  ]
-} else {
-  grit_defines += [
-    "-D",
-    "_chromium",
-    "-E",
-    "CHROMIUM_BUILD=chromium",
-  ]
-}
-
-if (is_chromeos) {
-  grit_defines += [
-    "-D",
-    "chromeos",
-    "-D",
-    "scale_factors=2x",
-  ]
-}
-
-if (is_desktop_linux) {
-  grit_defines += [
-    "-D",
-    "desktop_linux",
-  ]
-}
-
-if (toolkit_views) {
-  grit_defines += [
-    "-D",
-    "toolkit_views",
-  ]
-}
-
-if (use_aura) {
-  grit_defines += [
-    "-D",
-    "use_aura",
-  ]
-}
-
-if (use_ash) {
-  grit_defines += [
-    "-D",
-    "use_ash",
-  ]
-}
-
-if (use_nss_certs) {
-  grit_defines += [
-    "-D",
-    "use_nss_certs",
-  ]
-}
-
-if (use_ozone) {
-  grit_defines += [
-    "-D",
-    "use_ozone",
-  ]
-}
-
-if (enable_image_loader_extension) {
-  grit_defines += [
-    "-D",
-    "image_loader_extension",
-  ]
-}
-
-if (enable_remoting) {
-  grit_defines += [
-    "-D",
-    "remoting",
-  ]
-}
-
-if (is_android) {
-  grit_defines += [
-    "-t",
-    "android",
-    "-E",
-    "ANDROID_JAVA_TAGGED_ONLY=true",
-  ]
-}
-
-if (is_mac || is_ios) {
-  grit_defines += [
-    "-D",
-    "scale_factors=2x",
-  ]
-}
-
-if (is_ios) {
-  grit_defines += [
-    "-t",
-    "ios",
-
-    # iOS uses a whitelist to filter resources.
-    "-w",
-    rebase_path("//build/ios/grit_whitelist.txt", root_build_dir),
-  ]
-}
-
-if (enable_extensions) {
-  grit_defines += [
-    "-D",
-    "enable_extensions",
-  ]
-}
-if (enable_media_router) {
-  grit_defines += [
-    "-D",
-    "enable_media_router",
-  ]
-}
-if (enable_plugins) {
-  grit_defines += [
-    "-D",
-    "enable_plugins",
-  ]
-}
-if (enable_basic_printing || enable_print_preview) {
-  grit_defines += [
-    "-D",
-    "enable_printing",
-  ]
-  if (enable_print_preview) {
-    grit_defines += [
-      "-D",
-      "enable_print_preview",
-    ]
-  }
-}
-if (enable_themes) {
-  grit_defines += [
-    "-D",
-    "enable_themes",
-  ]
-}
-if (enable_app_list) {
-  grit_defines += [
-    "-D",
-    "enable_app_list",
-  ]
-}
-if (enable_settings_app) {
-  grit_defines += [
-    "-D",
-    "enable_settings_app",
-  ]
-}
-if (enable_google_now) {
-  grit_defines += [
-    "-D",
-    "enable_google_now",
-  ]
-}
-
-# Note: use_concatenated_impulse_responses is omitted. It is never used and
-# should probably be removed from GYP build.
-if (enable_webrtc) {
-  grit_defines += [
-    "-D",
-    "enable_webrtc",
-  ]
-}
-if (enable_hangout_services_extension) {
-  grit_defines += [
-    "-D",
-    "enable_hangout_services_extension",
-  ]
-}
-if (enable_task_manager) {
-  grit_defines += [
-    "-D",
-    "enable_task_manager",
-  ]
-}
-if (enable_notifications) {
-  grit_defines += [
-    "-D",
-    "enable_notifications",
-  ]
-}
-if (enable_wifi_bootstrapping) {
-  grit_defines += [
-    "-D",
-    "enable_wifi_bootstrapping",
-  ]
-}
-if (enable_service_discovery) {
-  grit_defines += [
-    "-D",
-    "enable_service_discovery",
-  ]
-}
-if (mac_views_browser) {
-  grit_defines += [
-    "-D",
-    "mac_views_browser",
-  ]
-}
-
-grit_resource_id_file = "//tools/gritsettings/resource_ids"
-grit_info_script = "//tools/grit/grit_info.py"
-
-template("grit") {
-  assert(defined(invoker.source),
-         "\"source\" must be defined for the grit template $target_name")
-
-  grit_inputs = [ invoker.source ]
-
-  if (defined(invoker.resource_ids)) {
-    resource_ids = invoker.resource_ids
-  } else {
-    resource_ids = grit_resource_id_file
-  }
-  if (resource_ids != "") {
-    # The script depends on the ID file. Only add this dependency if the ID
-    # file is specified.
-    grit_inputs += [ resource_ids ]
-  }
-
-  if (defined(invoker.output_dir)) {
-    output_dir = invoker.output_dir
-  } else {
-    output_dir = target_gen_dir
-  }
-
-  if (defined(invoker.output_name)) {
-    grit_output_name = invoker.output_name
-  } else {
-    grit_output_name = target_name
-  }
-
-  if (defined(invoker.depfile_dir)) {
-    depfile_dir = invoker.depfile_dir
-  } else {
-    depfile_dir = output_dir
-  }
-
-  # These are all passed as arguments to the script so have to be relative to
-  # the build directory.
-  if (resource_ids != "") {
-    resource_ids = rebase_path(resource_ids, root_build_dir)
-  }
-  rebased_output_dir = rebase_path(output_dir, root_build_dir)
-  source_path = rebase_path(invoker.source, root_build_dir)
-
-  if (defined(invoker.grit_flags)) {
-    grit_flags = invoker.grit_flags
-  } else {
-    grit_flags = []  # These are optional so default to empty list.
-  }
-
-  assert_files_flags = []
-
-  # We want to make sure the declared outputs actually match what Grit is
-  # writing. We write the list to a file (some of the output lists are long
-  # enough to not fit on a Windows command line) and ask Grit to verify those
-  # are the actual outputs at runtime.
-  asserted_list_file =
-      "$target_out_dir/${grit_output_name}_expected_outputs.txt"
-  write_file(asserted_list_file,
-             rebase_path(invoker.outputs, root_build_dir, output_dir))
-  assert_files_flags += [ "--assert-file-list=" +
-                          rebase_path(asserted_list_file, root_build_dir) ]
-  grit_outputs =
-      get_path_info(rebase_path(invoker.outputs, ".", output_dir), "abspath")
-
-  # The config and the action below get this visibility son only the generated
-  # source set can depend on them. The variable "target_name" will get
-  # overwritten inside the inner classes so we need to compute it here.
-  target_visibility = [ ":$target_name" ]
-
-  # The current grit setup makes an file in $output_dir/grit/foo.h that
-  # the source code expects to include via "grit/foo.h". It would be nice to
-  # change this to including absolute paths relative to the root gen directory
-  # (like "mycomponent/foo.h"). This config sets up the include path.
-  grit_config = target_name + "_grit_config"
-  config(grit_config) {
-    if (!defined(invoker.use_qualified_include) ||
-        !invoker.use_qualified_include) {
-      include_dirs = [ output_dir ]
-    }
-    visibility = target_visibility
-  }
-
-  grit_custom_target = target_name + "_grit"
-  action(grit_custom_target) {
-    script = "//tools/grit/grit.py"
-    inputs = grit_inputs
-
-    depfile = "$depfile_dir/${grit_output_name}_stamp.d"
-    outputs = [ "${depfile}.stamp" ] + grit_outputs
-
-    args = [
-      "-i",
-      source_path,
-      "build",
-    ]
-    if (resource_ids != "") {
-      args += [
-        "-f",
-        resource_ids,
-      ]
-    }
-    args += [
-              "-o",
-              rebased_output_dir,
-              "--depdir",
-              ".",
-              "--depfile",
-              rebase_path(depfile, root_build_dir),
-              "--write-only-new=1",
-              "--depend-on-stamp",
-            ] + grit_defines
-
-    # Add extra defines with -D flags.
-    if (defined(invoker.defines)) {
-      foreach(i, invoker.defines) {
-        args += [
-          "-D",
-          i,
-        ]
-      }
-    }
-
-    args += grit_flags + assert_files_flags
-
-    if (defined(invoker.visibility)) {
-      # This needs to include both what the invoker specified (since they
-      # probably include generated headers from this target), as well as the
-      # generated source set (since there's no guarantee that the visibility
-      # specified by the invoker includes our target).
-      #
-      # Only define visibility at all if the invoker specified it. Otherwise,
-      # we want to keep the public "no visibility specified" default.
-      visibility = target_visibility + invoker.visibility
-    }
-
-    deps = [
-      "//tools/grit:grit_sources",
-    ]
-    if (defined(invoker.deps)) {
-      deps += invoker.deps
-    }
-    if (defined(invoker.inputs)) {
-      inputs += invoker.inputs
-    }
-  }
-
-  # This is the thing that people actually link with, it must be named the
-  # same as the argument the template was invoked with.
-  source_set(target_name) {
-    # Since we generate a file, we need to be run before the targets that
-    # depend on us.
-    sources = grit_outputs
-
-    # Deps set on the template invocation will go on the action that runs
-    # grit above rather than this library. This target needs to depend on the
-    # action publicly so other scripts can take the outputs from the grit
-    # script as inputs.
-    public_deps = [
-      ":$grit_custom_target",
-    ]
-    public_configs = [ ":$grit_config" ]
-
-    if (defined(invoker.public_configs)) {
-      public_configs += invoker.public_configs
-    }
-
-    if (defined(invoker.configs)) {
-      configs += invoker.configs
-    }
-
-    if (defined(invoker.visibility)) {
-      visibility = invoker.visibility
-    }
-    output_name = grit_output_name
-  }
-}
diff --git a/build/secondary/tools/grit/repack.gni b/build/secondary/tools/grit/repack.gni
deleted file mode 100644
index 1030674c62e..00000000000
--- a/build/secondary/tools/grit/repack.gni
+++ /dev/null
@@ -1,47 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This file defines a template to invoke grit repack in a consistent manner.
-#
-# Parameters:
-#   sources  [required]
-#       List of pak files that need to be combined.
-#
-#   output  [required]
-#       File name (single string) of the output file.
-#
-#   repack_options  [optional]
-#       List of extra arguments to pass.
-#
-#   deps  [optional]
-#   visibility  [optional]
-#       Normal meaning.
-template("repack") {
-  action(target_name) {
-    assert(defined(invoker.sources), "Need sources for $target_name")
-    assert(defined(invoker.output), "Need output for $target_name")
-
-    if (defined(invoker.visibility)) {
-      visibility = invoker.visibility
-    }
-
-    script = "//tools/grit/grit/format/repack.py"
-
-    inputs = invoker.sources
-    outputs = [
-      invoker.output,
-    ]
-
-    args = []
-    if (defined(invoker.repack_options)) {
-      args += invoker.repack_options
-    }
-    args += [ rebase_path(invoker.output, root_build_dir) ]
-    args += rebase_path(invoker.sources, root_build_dir)
-
-    if (defined(invoker.deps)) {
-      deps = invoker.deps
-    }
-  }
-}
diff --git a/build/secondary/tools/grit/stamp_grit_sources.py b/build/secondary/tools/grit/stamp_grit_sources.py
deleted file mode 100644
index d43d4b8c7fd..00000000000
--- a/build/secondary/tools/grit/stamp_grit_sources.py
+++ /dev/null
@@ -1,55 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This script enumerates the files in the given directory, writing an empty
-# stamp file and a .d file listing the inputs required to make the stamp. This
-# allows us to dynamically depend on the grit sources without enumerating the
-# grit directory for every invocation of grit (which is what adding the source
-# files to every .grd file's .d file would entail) or shelling out to grit
-# synchronously during GN execution to get the list (which would be slow).
-#
-# Usage:
-#    stamp_grit_sources.py <directory> <stamp-file> <.d-file>
-
-import os
-import sys
-
-def GritSourceFiles(grit_root_dir):
-  files = []
-  for root, _, filenames in os.walk(grit_root_dir):
-    grit_src = [os.path.join(root, f) for f in filenames
-                if f.endswith('.py') and not f.endswith('_unittest.py')]
-    files.extend(grit_src)
-  files = [f.replace('\\', '/') for f in files]
-  return sorted(files)
-
-
-def WriteDepFile(dep_file, stamp_file, source_files):
-  with open(dep_file, "w") as f:
-    f.write(stamp_file)
-    f.write(": ")
-    f.write(' '.join(source_files))
-
-
-def WriteStampFile(stamp_file):
-  with open(stamp_file, "w"):
-    pass
-
-
-def main(argv):
-  if len(argv) != 4:
-    print "Error: expecting 3 args."
-    return 1
-
-  grit_root_dir = sys.argv[1]
-  stamp_file = sys.argv[2]
-  dep_file = sys.argv[3]
-
-  WriteStampFile(stamp_file)
-  WriteDepFile(dep_file, stamp_file, GritSourceFiles(grit_root_dir))
-  return 0
-
-
-if __name__ == '__main__':
-  sys.exit(main(sys.argv))
diff --git a/build/toolchain/fnl/BUILD.gn b/build/toolchain/fnl/BUILD.gn
deleted file mode 100644
index 1e4a075231e..00000000000
--- a/build/toolchain/fnl/BUILD.gn
+++ /dev/null
@@ -1,24 +0,0 @@
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import("//build/toolchain/gcc_toolchain.gni")
-
-declare_args() {
-  toolchain_prefix = ""
-}
-
-gcc_toolchain("target") {
-  assert(toolchain_prefix != "", "Must provide toolchain_prefix")
-
-  cc = "${toolchain_prefix}gcc"
-  cxx = "${toolchain_prefix}g++"
-  ar = "${toolchain_prefix}ar"
-  ld = cxx
-  readelf = "${toolchain_prefix}readelf"
-  nm = "${toolchain_prefix}nm"
-
-  toolchain_cpu = "${target_cpu}"
-  toolchain_os = "linux"
-  is_clang = is_clang
-}
diff --git a/build/toolchain/linux/BUILD.gn b/build/toolchain/linux/BUILD.gn
index c16e31c46b1..ae090b0fb0e 100644
--- a/build/toolchain/linux/BUILD.gn
+++ b/build/toolchain/linux/BUILD.gn
@@ -8,6 +8,10 @@ import("//build/toolchain/clang.gni")
 import("//build/toolchain/gcc_toolchain.gni")
 import("//build/toolchain/goma.gni")
 
+declare_args() {
+  toolchain_prefix = ""
+}
+
 if (use_goma) {
   assert(!use_ccache, "Goma and ccache can't be used together.")
   compiler_prefix = "$goma_dir/gomacc "
@@ -31,14 +35,23 @@ gcc_toolchain("arm") {
   is_clang = false
 }
 
+gcc_toolchain("arm64") {
+  cc = "${compiler_prefix}aarch64-linux-gnu-gcc"
+  cxx = "${compiler_prefix}aarch64-linux-gnu-g++"
+
+  ar = "aarch64-linux-gnu-ar"
+  ld = cxx
+  readelf = "aarch64-linux-gnu-readelf"
+  nm = "aarch64-linux-gnu-nm"
+
+  toolchain_cpu = "arm64"
+  toolchain_os = "linux"
+  is_clang = false
+}
+
 gcc_toolchain("clang_x86") {
-  if (use_clang_type_profiler) {
-    prefix = rebase_path("//third_party/llvm-allocated-type/Linux_ia32/bin",
-                         root_build_dir)
-  } else {
-    prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
-                         root_build_dir)
-  }
+  prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
+                       root_build_dir)
   cc = "${compiler_prefix}$prefix/clang"
   cxx = "${compiler_prefix}$prefix/clang++"
   readelf = "readelf"
@@ -53,7 +66,7 @@ gcc_toolchain("clang_x86") {
 
 gcc_toolchain("x86") {
   cc = "${compiler_prefix}gcc"
-  cxx = "$compiler_prefix}g++"
+  cxx = "${compiler_prefix}g++"
 
   readelf = "readelf"
   nm = "nm"
@@ -66,13 +79,8 @@ gcc_toolchain("x86") {
 }
 
 gcc_toolchain("clang_x64") {
-  if (use_clang_type_profiler) {
-    prefix = rebase_path("//third_party/llvm-allocated-type/Linux_x64/bin",
-                         root_build_dir)
-  } else {
-    prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
-                         root_build_dir)
-  }
+  prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
+                       root_build_dir)
   cc = "${compiler_prefix}$prefix/clang"
   cxx = "${compiler_prefix}$prefix/clang++"
 
@@ -102,14 +110,14 @@ gcc_toolchain("x64") {
 }
 
 gcc_toolchain("mipsel") {
-  cc = "mipsel-linux-gnu-gcc"
-  cxx = "mipsel-linux-gnu-g++"
-  ar = "mipsel-linux-gnu-ar"
+  cc = "${toolchain_prefix}gcc"
+  cxx = "${toolchain_prefix}g++"
+  ar = "${toolchain_prefix}ar"
   ld = cxx
-  readelf = "mipsel-linux-gnu-readelf"
-  nm = "mipsel-linux-gnu-nm"
+  readelf = "${toolchain_prefix}readelf"
+  nm = "${toolchain_prefix}nm"
 
-  toolchain_cpu = "mipsel"
+  toolchain_cpu = "${target_cpu}"
   toolchain_os = "linux"
-  is_clang = false
+  is_clang = is_clang
 }
diff --git a/runtime/BUILD.gn b/runtime/BUILD.gn
index df10d3a7228..afc963ab00a 100644
--- a/runtime/BUILD.gn
+++ b/runtime/BUILD.gn
@@ -2,10 +2,6 @@
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
-# TODO(zra): These build arguments should likely be moved to a gni file that is
-# included in BUILD.gn files that care about the values of the flags. For now,
-# since the GN build only happens as part of a Mojo build there is no need for
-# the indirection.
 declare_args() {
   # Instead of using is_debug, we introduce a different flag for specifying a
   # Debug build of Dart so that clients can still use a Release build of Dart
@@ -20,6 +16,10 @@ declare_args() {
   # CPU profiling features enabled.
   # 'release' - The VM is built to run with AOT compiled code with no developer
   # features enabled.
+  #
+  # These settings are only used for Flutter, at the moment. A standalone build
+  # of the Dart VM should leave this set to "develop", and should set
+  # 'is_debug', 'is_release', or 'is_product'.
   dart_runtime_mode = "develop"
 
   # Explicitly set the target architecture in case of precompilation. Leaving
@@ -36,8 +36,8 @@ config("dart_public_config") {
   ]
 }
 
-# Controls PRODUCT #define.
-config("dart_product_config") {
+# Adds PRODUCT define if Flutter has specified "release" for dart_runtime_mode
+config("dart_maybe_product_config") {
   defines = []
 
   if ((dart_runtime_mode != "develop") &&
@@ -56,8 +56,9 @@ config("dart_product_config") {
   }
 }
 
-# Controls DART_PRECOMPILED_RUNTIME #define.
-config("dart_precompiled_runtime_config") {
+# Adds the DART_PRECOMPILED_RUNTIME define if Flutter has specified "profile" or
+# "release" for dart_runtime_mode.
+config("dart_maybe_precompiled_runtime_config") {
   defines = []
 
   if ((dart_runtime_mode != "develop") &&
@@ -83,12 +84,22 @@ config("dart_precompiled_runtime_config") {
   }
 }
 
+config("dart_precompiled_runtime_config") {
+  defines = []
+  defines += ["DART_PRECOMPILED_RUNTIME"]
+}
+
 # Controls DART_PRECOMPILER #define.
 config("dart_precompiler_config") {
   defines = []
   defines += ["DART_PRECOMPILER"]
 }
 
+config("dart_no_snapshot_config") {
+  defines = []
+  defines += ["DART_NO_SNAPSHOT"]
+}
+
 config("dart_config") {
   defines = []
 
@@ -97,23 +108,39 @@ config("dart_config") {
   }
 
   if (dart_target_arch != "") {
-    if (dart_target_arch == "arm") {
+    if ((dart_target_arch == "arm") ||
+        (dart_target_arch == "simarm")) {
       defines += [ "TARGET_ARCH_ARM" ]
       if (target_os == "mac" || target_os == "ios") {
         defines += [ "TARGET_ABI_IOS" ]
       } else {
         defines += [ "TARGET_ABI_EABI" ]
       }
-    } else if (dart_target_arch == "arm64") {
+    } else if ((dart_target_arch == "armv6") ||
+               (dart_target_arch == "simarmv6")) {
+      defines += [ "TARGET_ARCH_ARM" ]
+      defines += [ "TARGET_ARCH_ARM_6" ]
+      defines += [ "TARGET_ABI_EABI" ]
+    } else if ((dart_target_arch == "armv5te") ||
+               (dart_target_arch == "simarmv5te")) {
+      defines += [ "TARGET_ARCH_ARM" ]
+      defines += [ "TARGET_ARCH_ARM_5TE" ]
+      defines += [ "TARGET_ABI_EABI" ]
+    } else if ((dart_target_arch == "arm64") ||
+               (dart_target_arch == "simarm64")) {
       defines += [ "TARGET_ARCH_ARM64" ]
-    } else if (dart_target_arch == "mips") {
+    } else if ((dart_target_arch == "mips") ||
+               (dart_target_arch == "simmips")) {
       defines += [ "TARGET_ARCH_MIPS" ]
     } else if (dart_target_arch == "x64") {
       defines += [ "TARGET_ARCH_X64" ]
     } else if (dart_target_arch == "ia32") {
       defines += [ "TARGET_ARCH_IA32" ]
-    } else if (dart_target_arch == "dbc") {
+    } else if ((dart_target_arch == "dbc") ||
+               (dart_target_arch == "simdbc") ||
+               (dart_target_arch == "simdbc64")) {
       defines += [ "TARGET_ARCH_DBC" ]
+      defines += [ "USING_SIMULATOR" ]
     } else  {
       print("Invalid |dart_target_arch|")
       assert(false)
@@ -159,31 +186,97 @@ config("dart_config") {
   }
 }
 
-static_library("libdart") {
-  configs += [":dart_config",
-              ":dart_product_config",
-              ":dart_precompiled_runtime_config"]
-  deps = [
+template("libdart_library") {
+  extra_configs = []
+  if (defined(invoker.extra_configs)) {
+    extra_configs += invoker.extra_configs
+  }
+  extra_deps = []
+  if (defined(invoker.extra_deps)) {
+    extra_deps += invoker.extra_deps
+  }
+  static_library(target_name) {
+    configs += [
+      ":dart_config",
+      ":dart_maybe_product_config"
+    ] + extra_configs
+    deps = [
+      "vm:libdart_platform",
+      "third_party/double-conversion/src:libdouble_conversion",
+      ":generate_version_cc_file",
+    ] + extra_deps
+    include_dirs = [
+      ".",
+    ]
+    public_configs = [":dart_public_config"]
+    sources = [
+      "include/dart_api.h",
+      "include/dart_mirrors_api.h",
+      "include/dart_native_api.h",
+      "include/dart_tools_api.h",
+      "vm/dart_api_impl.cc",
+      "vm/debugger_api_impl.cc",
+      "vm/mirrors_api_impl.cc",
+      "vm/native_api_impl.cc",
+      "vm/version.h",
+      "$target_gen_dir/version.cc",
+    ]
+    defines = [
+      "DART_SHARED_LIB",
+    ]
+  }
+}
+
+libdart_library("libdart") {
+  extra_configs = [
+    ":dart_maybe_precompiled_runtime_config"
+  ]
+  extra_deps = [
     "vm:libdart_lib",
     "vm:libdart_vm",
-    "third_party/double-conversion/src:libdouble_conversion",
-    ":generate_version_cc_file",
   ]
-  include_dirs = [
-    ".",
+}
+
+libdart_library("libdart_precompiled_runtime") {
+  extra_configs = [
+    ":dart_precompiled_runtime_config"
   ]
-  public_configs = [":dart_public_config"]
-  sources = [
-    "include/dart_api.h",
-    "include/dart_mirrors_api.h",
-    "include/dart_native_api.h",
-    "include/dart_tools_api.h",
-    "vm/dart_api_impl.cc",
-    "vm/debugger_api_impl.cc",
-    "vm/mirrors_api_impl.cc",
-    "vm/native_api_impl.cc",
-    "vm/version.h",
-    "$target_gen_dir/version.cc",
+  extra_deps = [
+    "vm:libdart_lib_precompiled_runtime",
+    "vm:libdart_vm_precompiled_runtime",
+  ]
+}
+
+libdart_library("libdart_nosnapshot") {
+  extra_configs = [
+    ":dart_no_snapshot_config",
+    ":dart_maybe_precompiled_runtime_config"
+  ]
+  extra_deps = [
+    "vm:libdart_lib_nosnapshot",
+    "vm:libdart_vm_nosnapshot",
+  ]
+}
+
+libdart_library("libdart_nosnapshot_precompiled_runtime") {
+  extra_configs = [
+    ":dart_no_snapshot_config",
+    ":dart_precompiled_runtime_config"
+  ]
+  extra_deps = [
+    "vm:libdart_lib_nosnapshot_precompiled_runtime",
+    "vm:libdart_vm_nosnapshot_precompiled_runtime",
+  ]
+}
+
+libdart_library("libdart_nosnapshot_with_precompiler") {
+  extra_configs = [
+    ":dart_no_snapshot_config",
+    ":dart_precompiler_config",
+  ]
+  extra_deps = [
+    "vm:libdart_lib_nosnapshot_with_precompiler",
+    "vm:libdart_vm_nosnapshot_with_precompiler",
   ]
 }
 
@@ -211,8 +304,7 @@ action("generate_version_cc_file") {
 
 executable("libdart_dependency_helper") {
   configs += [":dart_config",
-              ":dart_product_config",
-              ":dart_precompiled_runtime_config"]
+              ":dart_maybe_product_config"]
   deps = [
     "vm:libdart_lib_nosnapshot",
     "vm:libdart_lib",
diff --git a/runtime/bin/BUILD.gn b/runtime/bin/BUILD.gn
index 4c359bd5dd0..f09dd415b9a 100644
--- a/runtime/bin/BUILD.gn
+++ b/runtime/bin/BUILD.gn
@@ -6,6 +6,12 @@ declare_args() {
   # Whether to fall back to built-in root certificates when they cannot be
   # verified at the operating system level.
   dart_use_fallback_root_certificates = false
+
+  # The BUILD.gn file that we pull from chromium as part of zlib has a
+  # dependence on //base, which we don't pull in. In a standalone build of the
+  # VM, we set this to //runtime/bin/zlib where we have a BUILD.gn file without
+  # a dependence on //base.
+  dart_zlib_path = "//third_party/zlib"
 }
 
 resources_sources_gypi =
@@ -37,7 +43,6 @@ action("gen_resources_cc") {
   ] + rebase_path(sources, root_build_dir)
 }
 
-
 template("gen_library_src_path") {
   assert(defined(invoker.sources), "Need sources in $target_name")
   assert(defined(invoker.output), "Need output in $target_name")
@@ -51,17 +56,20 @@ template("gen_library_src_path") {
     outputs = [ invoker.output, ]
     name = invoker.name
     kind = invoker.kind
+    library_name = "dart:${name}"
+    if (defined(invoker.library_name)) {
+      library_name = invoker.library_name
+    }
     args = [
       "--output", rebase_path(invoker.output, root_build_dir),
       "--input_cc", rebase_path("builtin_in.cc", root_build_dir),
       "--include", "bin/builtin.h",
       "--var_name", "dart::bin::Builtin::${name}_${kind}_paths_",
-      "--library_name", "dart:${name}",] +
+      "--library_name", library_name,] +
       rebase_path(invoker.sources, root_build_dir)
   }
 }
 
-
 builtin_sources_gypi =
     exec_script("../../tools/gypi_to_gn.py",
                 [rebase_path("builtin_sources.gypi")],
@@ -75,7 +83,6 @@ gen_library_src_path("generate_builtin_cc_file") {
   output = "$target_gen_dir/builtin_gen.cc"
 }
 
-
 sdk_io_sources_gypi =
     exec_script("../../tools/gypi_to_gn.py",
                 [rebase_path("../../sdk/lib/io/io_sources.gypi")],
@@ -104,14 +111,105 @@ gen_library_src_path("generate_io_patch_cc_file") {
   output = "$target_gen_dir/io_patch_gen.cc"
 }
 
+gen_library_src_path("generate_html_cc_file") {
+  name = "html"
+  kind = "source"
+  sources = ["../../sdk/lib/html/dartium/html_dartium.dart"]
+  output = "$target_gen_dir/html_gen.cc"
+}
+
+gen_library_src_path("generate_html_common_cc_file") {
+  name = "html_common"
+  kind = "source"
+  sources = [
+    "../../sdk/lib/html/html_common/html_common.dart",
+    "../../sdk/lib/html/html_common/css_class_set.dart",
+    "../../sdk/lib/html/html_common/device.dart",
+    "../../sdk/lib/html/html_common/filtered_element_list.dart",
+    "../../sdk/lib/html/html_common/lists.dart",
+    "../../sdk/lib/html/html_common/conversions.dart",
+    "../../sdk/lib/html/html_common/conversions_dartium.dart",
+  ]
+  output = "$target_gen_dir/html_common_gen.cc"
+}
+
+gen_library_src_path("generate_js_cc_file") {
+  name = "js"
+  kind = "source"
+  sources = ["../../sdk/lib/js/dartium/js_dartium.dart"]
+  output = "$target_gen_dir/js_gen.cc"
+}
+
+gen_library_src_path("generate_blink_cc_file") {
+  name = "_blink"
+  kind = "source"
+  sources = ["../../sdk/lib/_blink/dartium/_blink_dartium.dart"]
+  output = "$target_gen_dir/blink_gen.cc"
+}
+
+gen_library_src_path("generate_indexed_db_cc_file") {
+  name = "indexed_db"
+  kind = "source"
+  sources = ["../../sdk/lib/indexed_db/dartium/indexed_db_dartium.dart"]
+  output = "$target_gen_dir/indexed_db_gen.cc"
+}
+
+gen_library_src_path("generate_cached_patches_cc_file") {
+  name = "cached_patches"
+  library_name = "cached_patches.dart"
+  kind = "sources"
+  sources = ["../../sdk/lib/js/dartium/cached_patches.dart"]
+  output = "$target_gen_dir/cached_patches_gen.cc"
+}
+
+gen_library_src_path("generate_web_gl_cc_file") {
+  name = "web_gl"
+  kind = "source"
+  sources = ["../../sdk/lib/web_gl/dartium/web_gl_dartium.dart"]
+  output = "$target_gen_dir/web_gl_gen.cc"
+}
+
+gen_library_src_path("generate_metadata_cc_file") {
+  name = "metadata"
+  library_name = "metadata.dart"
+  kind = "source"
+  sources = ["../../sdk/lib/html/html_common/metadata.dart"]
+  output = "$target_gen_dir/metadata_gen.cc"
+}
+
+gen_library_src_path("generate_web_sql_cc_file") {
+  name = "web_sql"
+  kind = "source"
+  sources = ["../../sdk/lib/web_sql/dartium/web_sql_dartium.dart"]
+  output = "$target_gen_dir/web_sql_gen.cc"
+}
+
+gen_library_src_path("generate_svg_cc_file") {
+  name = "svg"
+  kind = "source"
+  sources = ["../../sdk/lib/svg/dartium/svg_dartium.dart"]
+  output = "$target_gen_dir/svg_gen.cc"
+}
+
+gen_library_src_path("generate_web_audio_cc_file") {
+  name = "web_audio"
+  kind = "source"
+  sources = ["../../sdk/lib/web_audio/dartium/web_audio_dartium.dart"]
+  output = "$target_gen_dir/web_audio_gen.cc"
+}
 
 config("libdart_builtin_config") {
   libs = [
     "dl",
   ]
+  if (is_android) {
+    libs += [
+      "android",
+      "log",
+    ]
+  }
 }
 
-
 builtin_impl_sources_gypi =
     exec_script("../../tools/gypi_to_gn.py",
                 [rebase_path("builtin_impl_sources.gypi")],
@@ -119,12 +217,24 @@ builtin_impl_sources_gypi =
                 ["builtin_impl_sources.gypi"])
 
 static_library("libdart_builtin") {
-  configs += ["..:dart_config", "..:dart_product_config"]
+  configs += ["..:dart_config",
+              "..:dart_maybe_product_config"]
   public_configs = [":libdart_builtin_config"]
   deps = [
     ":generate_builtin_cc_file",
     ":generate_io_cc_file",
     ":generate_io_patch_cc_file",
+    ":generate_html_cc_file",
+    ":generate_html_common_cc_file",
+    ":generate_js_cc_file",
+    ":generate_blink_cc_file",
+    ":generate_indexed_db_cc_file",
+    ":generate_cached_patches_cc_file",
+    ":generate_web_gl_cc_file",
+    ":generate_metadata_cc_file",
+    ":generate_web_sql_cc_file",
+    ":generate_svg_cc_file",
+    ":generate_web_audio_cc_file",
   ]
   include_dirs = [
     "..",
@@ -139,74 +249,6 @@ static_library("libdart_builtin") {
   ] + builtin_impl_sources_gypi.sources
 }
 
-
-static_library("libdart_nosnapshot") {
-  configs += ["..:dart_config",
-              "..:dart_product_config",
-              "..:dart_precompiled_runtime_config"]
-  deps = [
-    "../vm:libdart_lib_nosnapshot",
-    "../vm:libdart_vm_nosnapshot",
-    "../vm:libdart_platform",
-    "../third_party/double-conversion/src:libdouble_conversion",
-    "..:generate_version_cc_file",
-  ]
-
-  sources = [
-    "../include/dart_api.h",
-    "../include/dart_mirrors_api.h",
-    "../include/dart_native_api.h",
-    "../include/dart_tools_api.h",
-    "../vm/dart_api_impl.cc",
-    "../vm/debugger_api_impl.cc",
-    "../vm/mirrors_api_impl.cc",
-    "../vm/native_api_impl.cc",
-    "$target_gen_dir/../version.cc",
-  ]
-
-  include_dirs = [
-    "..",
-  ]
-
-  defines = [
-    "DART_SHARED_LIB",
-  ]
-}
-
-
-static_library("libdart_nosnapshot_with_precompiler") {
-  configs += ["..:dart_config",
-              "..:dart_product_config",
-              "..:dart_precompiler_config"]
-  deps = [
-    "../vm:libdart_lib_nosnapshot_with_precompiler",
-    "../vm:libdart_vm_nosnapshot_with_precompiler",
-    "../vm:libdart_platform",
-    "../third_party/double-conversion/src:libdouble_conversion",
-    "..:generate_version_cc_file",
-  ]
-
-  sources = [
-    "../include/dart_api.h",
-    "../include/dart_mirrors_api.h",
-    "../include/dart_native_api.h",
-    "../include/dart_tools_api.h",
-    "../vm/dart_api_impl.cc",
-    "../vm/debugger_api_impl.cc",
-    "../vm/mirrors_api_impl.cc",
-    "../vm/native_api_impl.cc",
-    "$target_gen_dir/../version.cc",
-  ]
-
-  include_dirs = [
-    "..",
-  ]
-
-  defines = [
-    "DART_SHARED_LIB",
-  ]
-}
-
 io_impl_sources_gypi =
     exec_script("../../tools/gypi_to_gn.py",
                 [ rebase_path("io_impl_sources.gypi") ],
@@ -215,7 +257,7 @@ io_impl_sources_gypi =
 
 executable("gen_snapshot") {
   configs += ["..:dart_config",
-              "..:dart_product_config",
+              "..:dart_maybe_product_config",
               "..:dart_precompiler_config"]
   deps = [
     ":gen_resources_cc",
@@ -224,7 +266,7 @@ executable("gen_snapshot") {
     ":generate_io_cc_file",
     ":generate_io_patch_cc_file",
     ":libdart_builtin",
-    ":libdart_nosnapshot_with_precompiler",
+    "..:libdart_nosnapshot_with_precompiler",
   ]
 
   sources = [
@@ -260,11 +302,11 @@ executable("gen_snapshot") {
 # (without secure sockets) suitable for linking with gen_snapshot.
 source_set("gen_snapshot_dart_io") {
   configs += ["..:dart_config",
-              "..:dart_product_config",
+              "..:dart_maybe_product_config",
               "..:dart_precompiler_config"]
 
   deps = [
-    "//third_party/zlib",
+    "$dart_zlib_path",
   ]
 
   custom_sources_filter = [
@@ -299,22 +341,16 @@ source_set("gen_snapshot_dart_io") {
 
 source_set("libdart_embedder_noio") {
   configs += ["..:dart_config",
-              "..:dart_product_config",
-              "..:dart_precompiled_runtime_config"]
+              "..:dart_maybe_product_config"]
   deps = [
     "..:libdart",
-    "../vm:libdart_platform",
   ]
 }
 
-
-# A source set for the implementation of 'dart:io' library
-# (without secure sockets).
+# A source set for the implementation of 'dart:io' library.
 source_set("embedded_dart_io") {
   configs += ["..:dart_config",
-              "..:dart_product_config",
-              "..:dart_precompiled_runtime_config"]
-
+              "..:dart_maybe_product_config"]
   custom_sources_filter = [
     "*_test.cc",
     "*_test.h",
@@ -330,6 +366,7 @@ source_set("embedded_dart_io") {
   }
   set_sources_assignment_filter(custom_sources_filter)
 
+  defines = []
   if (is_mac || is_ios) {
     libs = [
       "CoreFoundation.framework",
@@ -337,18 +374,13 @@ source_set("embedded_dart_io") {
       "Security.framework",
     ]
   } else if (defined(is_fuchsia) && is_fuchsia) {
-    defines = [
+    defines += [
       "DART_IO_SECURE_SOCKET_DISABLED"
     ]
   } else {
     deps = [
       "//third_party/boringssl",
     ]
-    if (is_linux && !dart_use_fallback_root_certificates) {
-        defines = [
-          "DART_IO_ROOT_CERTS_DISABLED"
-        ]
-    }
   }
 
   sources = io_impl_sources_gypi.sources + builtin_impl_sources_gypi.sources
@@ -366,8 +398,14 @@ source_set("embedded_dart_io") {
     "log.h",
   ]
 
-  if (is_linux && dart_use_fallback_root_certificates) {
-    sources += [ "//third_party/root_certificates/root_certificates.cc"]
+  if (is_linux || is_win) {
+    if (dart_use_fallback_root_certificates) {
+      sources += [ "//third_party/root_certificates/root_certificates.cc"]
+    } else {
+      defines += [
+        "DART_IO_ROOT_CERTS_DISABLED",
+      ]
+    }
   }
 
   include_dirs = [
@@ -376,7 +414,6 @@ source_set("embedded_dart_io") {
   ]
 }
 
-
 action("generate_snapshot_bin") {
   deps = [
     "../bin:gen_snapshot($host_toolchain)",
@@ -409,7 +446,6 @@ action("generate_snapshot_bin") {
   ]
 }
 
-
 action("generate_snapshot_file") {
   deps = [
     ":generate_snapshot_bin",
@@ -440,7 +476,6 @@ action("generate_snapshot_file") {
   ]
 }
 
-
 source_set("dart_snapshot_cc") {
   sources = [
     "$root_gen_dir/dart_snapshot.cc",
@@ -451,123 +486,99 @@ source_set("dart_snapshot_cc") {
   ]
 }
 
+template("dart_executable") {
+  extra_configs = []
+  if (defined(invoker.extra_configs)) {
+    extra_configs += invoker.extra_configs
+  }
+  extra_deps = []
+  if (defined(invoker.extra_deps)) {
+    extra_deps += invoker.extra_deps
+  }
+  extra_defines = []
+  if (defined(invoker.extra_defines)) {
+    extra_defines = invoker.extra_defines
+  }
+  extra_sources = []
+  if (defined(invoker.extra_sources)) {
+    extra_sources += invoker.extra_sources
+  }
+  executable(target_name) {
+    configs += [
+      "..:dart_config",
+      "..:dart_maybe_product_config"
+    ] + extra_configs
+
+    deps = [
+      ":gen_resources_cc",
+      ":embedded_dart_io",
+      ":libdart_builtin",
+      "$dart_zlib_path",
+    ] + extra_deps
+
+    defines = extra_defines
+
+    sources = [
+      "main.cc",
+      "vmservice_impl.cc",
+      "vmservice_impl.h",
+      "$target_gen_dir/resources_gen.cc",
+    ] + extra_sources
+
+    include_dirs = [
+      "..",
+      "//third_party",
+    ]
+
+    ldflags = [
+      "-rdynamic",
+    ]
+  }
+}
+
+if (!defined(is_fuchsia) || !is_fuchsia) {
+  dart_executable("dart") {
+    extra_deps = [
+      "..:libdart",
+      ":dart_snapshot_cc",
+      "../observatory:standalone_observatory_archive",
+    ]
+  }
+
+  dart_executable("dart_precompiled_runtime") {
+    extra_configs = [
+      "..:dart_precompiled_runtime_config"
+    ]
+    extra_deps = [
+      "..:libdart_precompiled_runtime",
+      ":dart_snapshot_cc",
+      "../observatory:standalone_observatory_archive",
+    ]
+  }
+}
+
+dart_executable("dart_bootstrap") {
+  extra_configs = [
+    "..:dart_precompiler_config",
+    "..:dart_no_snapshot_config",
+  ]
+  extra_deps = [
+    "..:libdart",
+  ]
+  extra_defines = [
+    "NO_OBSERVATORY",
+  ]
+  extra_sources = [
+    "observatory_assets_empty.cc",
+    "snapshot_empty.cc",
+  ]
+}
+
 if (defined(is_fuchsia) && is_fuchsia) {
   copy("hello_fuchsia") {
     sources = [ "../tests/vm/dart/hello_fuchsia_test.dart" ]
     outputs = [ "$root_out_dir/hello_fuchsia.dart" ]
   }
-}
-
-executable("dart_no_observatory") {
-  configs += ["..:dart_config",
-              "..:dart_product_config",
-              "..:dart_precompiled_runtime_config",]
-  deps = [
-    ":gen_resources_cc",
-    ":embedded_dart_io",
-    ":libdart_builtin",
-    "../vm:libdart_platform",
-    "..:libdart",
-    ":dart_snapshot_cc",
-    "//third_party/zlib",
-  ]
-
-  if (defined(is_fuchsia) && is_fuchsia) {
-    deps += [
-      ":hello_fuchsia",
-    ]
-  }
-
-  defines = [
-    "NO_OBSERVATORY",
-  ]
-
-  sources = [
-    "main.cc",
-    "observatory_assets_empty.cc",
-    "vmservice_impl.cc",
-    "vmservice_impl.h",
-    "$target_gen_dir/resources_gen.cc",
-  ]
-
-  include_dirs = [
-    "..",
-    "//third_party",
-  ]
-}
-
-
-if (defined(is_fuchsia) && is_fuchsia) {
-  action("generate_snapshot_test_dat_file") {
-    snapshot_test_dat_file = "$root_gen_dir/snapshot_test.dat"
-    snapshot_test_in_dat_file = "../vm/snapshot_test_in.dat"
-    snapshot_test_dart_file = "../vm/snapshot_test.dart"
-    inputs = [
-      "../tools/create_string_literal.py",
-      snapshot_test_in_dat_file,
-      snapshot_test_dart_file,
-    ]
-
-    outputs = [
-      snapshot_test_dat_file,
-    ]
-
-    script = "../tools/create_string_literal.py"
-    args = [
-      "--output",
-      rebase_path(snapshot_test_dat_file),
-      "--input_cc",
-      rebase_path(snapshot_test_in_dat_file),
-      "--include",
-      "INTENTIONALLY_LEFT_BLANK",
-      "--var_name",
-      "INTENTIONALLY_LEFT_BLANK_TOO",
-      rebase_path(snapshot_test_dart_file),
-    ]
-  }
-
-  executable("run_vm_tests") {
-    testonly = true
-    configs += ["..:dart_config",
-                "..:dart_product_config",
-                "..:dart_precompiled_runtime_config",]
-    deps = [
-      "..:libdart",
-      ":libdart_builtin",
-      ":embedded_dart_io",
-      ":dart_snapshot_cc",
-      ":generate_snapshot_test_dat_file",
-      "../vm:libdart_platform",
-      "//third_party/zlib",
-    ]
-    include_dirs = [
-      "..",
-      "$target_gen_dir",
-    ]
-    defines = [
-      "TESTING",
-    ]
-
-    vm_tests_list = exec_script("../../tools/gypi_to_gn.py",
-                                  [rebase_path("../vm/vm_sources.gypi"),
-                                   "--keep_only=_test.cc",
-                                   "--keep_only=_test.h",],
-                                  "scope",
-                                  ["../vm/vm_sources.gypi"])
-    vm_tests = rebase_path(vm_tests_list.sources, ".", "../vm")
-
-    builtin_impl_tests_list =
-        exec_script("../../tools/gypi_to_gn.py",
-                    [rebase_path("builtin_impl_sources.gypi"),
-                     "--keep_only=_test.cc",
-                     "--keep_only=_test.h",],
-                    "scope",
-                    ["builtin_impl_sources.gypi"])
-
-    sources = [
-      "run_vm_tests.cc",
-    ] + builtin_impl_tests_list.sources + vm_tests
-  }
 
   executable("run_vm_tests_fuchsia") {
     testonly = true
@@ -581,4 +592,138 @@ if (defined(is_fuchsia) && is_fuchsia) {
       "runtime",
     ]
   }
-}  # defined(is_fuchsia) && is_fuchsia
+}
+
+# This is only needed for the Fuchsia target build until the Observatory is
+# supported.
+dart_executable("dart_no_observatory") {
+  extra_deps = [
+    "..:libdart",
+    ":dart_snapshot_cc",
+  ]
+  if (defined(is_fuchsia) && is_fuchsia) {
+    extra_deps += [ ":hello_fuchsia" ]
+  }
+  extra_defines = [
+    "NO_OBSERVATORY",
+  ]
+  extra_sources = [
+    "observatory_assets_empty.cc",
+  ]
+}
+
+executable("process_test") {
+  sources = [
+    "process_test.cc",
+  ]
+}
+
+action("generate_snapshot_test_dat_file") {
+  snapshot_test_dat_file = "$root_gen_dir/snapshot_test.dat"
+  snapshot_test_in_dat_file = "../vm/snapshot_test_in.dat"
+  snapshot_test_dart_file = "../vm/snapshot_test.dart"
+  inputs = [
+    "../tools/create_string_literal.py",
+    snapshot_test_in_dat_file,
+    snapshot_test_dart_file,
+  ]
+
+  outputs = [
+    snapshot_test_dat_file,
+  ]
+
+  script = "../tools/create_string_literal.py"
+  args = [
+    "--output",
+    rebase_path(snapshot_test_dat_file),
+    "--input_cc",
+    rebase_path(snapshot_test_in_dat_file),
+    "--include",
+    "INTENTIONALLY_LEFT_BLANK",
+    "--var_name",
+    "INTENTIONALLY_LEFT_BLANK_TOO",
+    rebase_path(snapshot_test_dart_file),
+  ]
+}
+
+executable("run_vm_tests") {
+  configs += ["..:dart_config",
+              "..:dart_maybe_product_config"]
+  deps = [
+    "..:libdart",
+    ":libdart_builtin",
+    ":embedded_dart_io",
+    ":dart_snapshot_cc",
+    ":generate_snapshot_test_dat_file",
+    "$dart_zlib_path",
+  ]
+  include_dirs = [
+    "..",
+    "$target_gen_dir",
+  ]
+  defines = [
+    "TESTING",
+  ]
+
+  # The VM sources are already included in libdart, so we just want to add in
+  # the tests here.
+  vm_tests_list = exec_script("../../tools/gypi_to_gn.py",
+                                [rebase_path("../vm/vm_sources.gypi"),
+                                 "--keep_only=_test.cc",
+                                 "--keep_only=_test.h",],
+                                "scope",
+                                ["../vm/vm_sources.gypi"])
+  vm_tests = rebase_path(vm_tests_list.sources, ".", "../vm")
+
+  builtin_impl_tests_list =
+      exec_script("../../tools/gypi_to_gn.py",
+                  [rebase_path("builtin_impl_sources.gypi"),
+                   "--keep_only=_test.cc",
+                   "--keep_only=_test.h",],
+                  "scope",
+                  ["builtin_impl_sources.gypi"])
+
+  sources = [
+    "run_vm_tests.cc",
+  ] + builtin_impl_tests_list.sources + vm_tests
+
+  ldflags = [
+    "-rdynamic",
+  ]
+}
+
+if (!defined(is_fuchsia) || !is_fuchsia) {
+  shared_library("test_extension") {
+    deps = [
+      ":dart",
+    ]
+    sources = [
+      "test_extension.c",
+      "test_extension_dllmain_win.cc",
+    ]
+    include_dirs = [
+      "..",
+    ]
+    defines = [
+      # The only effect of DART_SHARED_LIB is to export the Dart API.
+      "DART_SHARED_LIB",
+    ]
+  }
+
+  shared_library("sample_extension") {
+    deps = [
+      ":dart",
+    ]
+    sources = [
+      "../../samples/sample_extension/sample_extension.cc",
+      "../../samples/sample_extension/sample_extension_dllmain_win.cc",
+    ]
+    include_dirs = [
+      "..",
+    ]
+    defines = [
+      # The only effect of DART_SHARED_LIB is to export the Dart API.
+      "DART_SHARED_LIB",
+    ]
+  }
+}
diff --git a/runtime/bin/bin.gypi b/runtime/bin/bin.gypi
index a31cb93bd45..650f587393e 100644
--- a/runtime/bin/bin.gypi
+++ b/runtime/bin/bin.gypi
@@ -290,7 +290,7 @@
         '--output', '<(blink_cc_file)',
         '--input_cc', '<(builtin_in_cc_file)',
         '--include', 'bin/builtin.h',
-        '--var_name', 'dart::bin::Builtin::blink_source_paths_',
+        '--var_name', 'dart::bin::Builtin::_blink_source_paths_',
         '--library_name', 'dart:_blink',
         '<@(_sources)',
         ],
@@ -322,7 +322,7 @@
         '--output', '<(indexeddb_cc_file)',
         '--input_cc', '<(builtin_in_cc_file)',
         '--include', 'bin/builtin.h',
-        '--var_name', 'dart::bin::Builtin::indexeddb_source_paths_',
+        '--var_name', 'dart::bin::Builtin::indexed_db_source_paths_',
         '--library_name', 'dart:indexed_db',
         '<@(_sources)',
         ],
@@ -450,7 +450,7 @@
         '--output', '<(websql_cc_file)',
         '--input_cc', '<(builtin_in_cc_file)',
         '--include', 'bin/builtin.h',
-        '--var_name', 'dart::bin::Builtin::websql_source_paths_',
+        '--var_name', 'dart::bin::Builtin::web_sql_source_paths_',
         '--library_name', 'dart:web_sql',
         '<@(_sources)',
         ],
@@ -514,7 +514,7 @@
         '--output', '<(webaudio_cc_file)',
         '--input_cc', '<(builtin_in_cc_file)',
         '--include', 'bin/builtin.h',
-        '--var_name', 'dart::bin::Builtin::webaudio_source_paths_',
+        '--var_name', 'dart::bin::Builtin::web_audio_source_paths_',
         '--library_name', 'dart:web_audio',
         '<@(_sources)',
         ],
diff --git a/runtime/bin/builtin.cc b/runtime/bin/builtin.cc
index 2c303a17d23..b3215bbfb8f 100644
--- a/runtime/bin/builtin.cc
+++ b/runtime/bin/builtin.cc
@@ -25,14 +25,14 @@ Builtin::builtin_lib_props Builtin::builtin_libraries_[] = {
   { "dart:html_common", html_common_source_paths_, NULL, NULL, true},
   { "dart:js", js_source_paths_, NULL, NULL, true},
   { "dart:js_util", js_util_source_paths_, NULL, NULL, true},
-  { "dart:_blink", blink_source_paths_, NULL, NULL, true },
-  { "dart:indexed_db", indexeddb_source_paths_, NULL, NULL, true },
+  { "dart:_blink", _blink_source_paths_, NULL, NULL, true },
+  { "dart:indexed_db", indexed_db_source_paths_, NULL, NULL, true },
   { "cached_patches.dart", cached_patches_source_paths_, NULL, NULL, true },
   { "dart:web_gl", web_gl_source_paths_, NULL, NULL, true },
   { "metadata.dart", metadata_source_paths_, NULL, NULL, true },
-  { "dart:web_sql", websql_source_paths_, NULL, NULL, true },
+  { "dart:web_sql", web_sql_source_paths_, NULL, NULL, true },
   { "dart:svg", svg_source_paths_, NULL, NULL, true },
-  { "dart:web_audio", webaudio_source_paths_, NULL, NULL, true },
+  { "dart:web_audio", web_audio_source_paths_, NULL, NULL, true },
 #endif  // defined(DART_NO_SNAPSHOT)
 
   // End marker.
diff --git a/runtime/bin/builtin.h b/runtime/bin/builtin.h
index d90223af734..d7e1e4c2268 100644
--- a/runtime/bin/builtin.h
+++ b/runtime/bin/builtin.h
@@ -75,14 +75,14 @@ class Builtin {
   static const char* html_common_source_paths_[];
   static const char* js_source_paths_[];
   static const char* js_util_source_paths_[];
-  static const char* blink_source_paths_[];
-  static const char* indexeddb_source_paths_[];
+  static const char* _blink_source_paths_[];
+  static const char* indexed_db_source_paths_[];
   static const char* cached_patches_source_paths_[];
   static const char* web_gl_source_paths_[];
   static const char* metadata_source_paths_[];
-  static const char* websql_source_paths_[];
+  static const char* web_sql_source_paths_[];
   static const char* svg_source_paths_[];
-  static const char* webaudio_source_paths_[];
+  static const char* web_audio_source_paths_[];
 
   static Dart_Port load_port_;
   static const int num_libs_;
diff --git a/runtime/bin/zlib/BUILD.gn b/runtime/bin/zlib/BUILD.gn
new file mode 100644
index 00000000000..ad78238347c
--- /dev/null
+++ b/runtime/bin/zlib/BUILD.gn
@@ -0,0 +1,56 @@
+# Copyright (c) 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("zlib_config") {
+  include_dirs = [ "//third_party/zlib" ]
+}
+
+static_library("zlib") {
+  if (!is_win) {
+    # Don't stomp on "libzlib" on other platforms.
+    output_name = "chrome_zlib"
+  }
+
+  zlib_path = "//third_party/zlib"
+  sources = [
+    "$zlib_path/adler32.c",
+    "$zlib_path/compress.c",
+    "$zlib_path/crc32.c",
+    "$zlib_path/crc32.h",
+    "$zlib_path/deflate.c",
+    "$zlib_path/deflate.h",
+    "$zlib_path/gzclose.c",
+    "$zlib_path/gzguts.h",
+    "$zlib_path/gzlib.c",
+    "$zlib_path/gzread.c",
+    "$zlib_path/gzwrite.c",
+    "$zlib_path/infback.c",
+    "$zlib_path/inffast.c",
+    "$zlib_path/inffast.h",
+    "$zlib_path/inffixed.h",
+    "$zlib_path/inflate.c",
+    "$zlib_path/inflate.h",
+    "$zlib_path/inftrees.c",
+    "$zlib_path/inftrees.h",
+    "$zlib_path/mozzconf.h",
+    "$zlib_path/trees.c",
+    "$zlib_path/trees.h",
+    "$zlib_path/uncompr.c",
+    "$zlib_path/zconf.h",
+    "$zlib_path/zlib.h",
+    "$zlib_path/zutil.c",
+    "$zlib_path/zutil.h",
+  ]
+
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+
+  all_dependent_configs = [ ":zlib_config" ]
+
+  if (is_clang) {
+    cflags = [
+      "-Wno-shift-negative-value",
+    ]
+  }
+}
diff --git a/runtime/observatory/.packages b/runtime/observatory/.packages
index 2a318029ebd..4730e6290d2 100644
--- a/runtime/observatory/.packages
+++ b/runtime/observatory/.packages
@@ -1,4 +1,4 @@
-# Generated by pub on 2016-09-22 14:19:01.104115.
+# Generated by pub on 2016-09-23 00:19:32.016148.
 analyzer:../../third_party/observatory_pub_packages/packages/analyzer/lib/
 args:../../third_party/observatory_pub_packages/packages/args/lib/
 async:../../third_party/observatory_pub_packages/packages/async/lib/
diff --git a/runtime/observatory/BUILD.gn b/runtime/observatory/BUILD.gn
index 3943253ca45..a476414b477 100644
--- a/runtime/observatory/BUILD.gn
+++ b/runtime/observatory/BUILD.gn
@@ -41,23 +41,24 @@ action("write_observatory_pubspec_yaml") {
     rebase_path("pubspec.yaml"),
   ]
 
+  current_dir = rebase_path(".", "//")
   args = [
     "--silent=True",
     "--pub-executable",
     dart_host_pub_exe,
     "--directory",
-    rebase_path("$root_gen_dir/observatory_copy/dart/runtime/observatory/"),
+    rebase_path("$root_gen_dir/observatory_copy/$current_dir/"),
     "--command",
     "rewrite",
     rebase_path("../observatory/pubspec.yaml"),
     rebase_path(
-        "$root_gen_dir/observatory_copy/dart/runtime/observatory/pubspec.yaml"),
+        "$root_gen_dir/observatory_copy/$current_dir/pubspec.yaml"),
     "../../third_party/",
     rebase_path("../../third_party/"),
   ]
 
   outputs = [
-    "$root_gen_dir/observatory_copy/dart/runtime/observatory/pubspec.yaml",
+    "$root_gen_dir/observatory_copy/$current_dir/pubspec.yaml",
   ]
 }
 
@@ -68,9 +69,10 @@ action("copy_observatory_deps") {
 
   script = "../../tools/observatory_tool.py"
 
+  current_dir = rebase_path(".", "//")
   inputs = [
     script,
-    "$root_gen_dir/observatory_copy/dart/runtime/observatory/pubspec.yaml",
+    "$root_gen_dir/observatory_copy/$current_dir/pubspec.yaml",
   ]
 
   args = [
@@ -78,23 +80,24 @@ action("copy_observatory_deps") {
     "--pub-executable",
     dart_host_pub_exe,
     "--stamp",
-    rebase_path("$root_gen_dir/observatory_copy/dart/runtime/observatory/packages.stamp"),
+    rebase_path("$root_gen_dir/observatory_copy/$current_dir/packages.stamp"),
     "--directory",
-    rebase_path("$root_gen_dir/observatory_copy/dart/runtime/observatory/"),
+    rebase_path("$root_gen_dir/observatory_copy/$current_dir/"),
     "--command",
     "get",
   ]
 
   outputs = [
-    "$root_gen_dir/observatory_copy/dart/runtime/observatory/packages.stamp",
+    "$root_gen_dir/observatory_copy/$current_dir/packages.stamp",
   ]
 }
 
 action("pub_build_observatory") {
+  current_dir = rebase_path(".", "//")
   sources =
       rebase_path(observatory_sources_gypi.sources,
                   "",
-                  "$root_gen_dir/observatory_copy/dart/runtime/observatory")
+                  "$root_gen_dir/observatory_copy/$current_dir")
 
   deps = [
     ":copy_observatory",
@@ -105,7 +108,7 @@ action("pub_build_observatory") {
 
   inputs = [
     script,
-    "$root_gen_dir/observatory_copy/dart/runtime/observatory/packages.stamp",
+    "$root_gen_dir/observatory_copy/$current_dir/packages.stamp",
   ]
   inputs += sources
 
@@ -114,7 +117,7 @@ action("pub_build_observatory") {
     "--pub-executable",
     dart_host_pub_exe,
     "--directory",
-    rebase_path("$root_gen_dir/observatory_copy/dart/runtime/observatory/"),
+    rebase_path("$root_gen_dir/observatory_copy/$current_dir/"),
     "--command",
     "build",
     rebase_path("$root_out_dir/observatory/build"),
@@ -152,41 +155,70 @@ action("deploy_observatory") {
   ]
 }
 
-action("archive_observatory") {
-  deps = [
-    ":deploy_observatory",
-  ]
+template("observatory_archive") {
+  assert(defined(invoker.inner_namespace),
+         "Need inner_namespace in $target_name")
+  assert(defined(invoker.outer_namespace),
+         "Need outer_namespace in $target_name")
+  action(target_name) {
+    deps = [
+      ":deploy_observatory",
+    ]
 
-  script = "../tools/create_archive.py"
+    script = "../tools/create_archive.py"
 
   inputs = [
     script,
     "$root_out_dir/observatory/deployed/web/main.dart.js",
   ]
 
-  args = [
-    "--output",
-    rebase_path("$root_gen_dir/observatory/observatory_archive.cc"),
-    "--tar_output",
-    rebase_path("$root_gen_dir/observatory/observatory_archive.tar"),
-    "--outer_namespace", "dart",
-    "--inner_namespace", "observatory",
-    "--name", "observatory_assets_archive",
-    "--client_root", rebase_path("$root_out_dir/observatory/deployed/web/"),
-  ]
+    inner_namespace = invoker.inner_namespace
+    outer_namespace = invoker.outer_namespace
+    output_name = target_name
+    args = [
+      "--output",
+      rebase_path("$root_gen_dir/observatory/${output_name}.cc"),
+      "--tar_output",
+      rebase_path("$root_gen_dir/observatory/${output_name}.tar"),
+      "--outer_namespace", outer_namespace,
+      "--inner_namespace", inner_namespace,
+      "--name", "observatory_assets_archive",
+      "--client_root", rebase_path("$root_out_dir/observatory/deployed/web/"),
+    ]
 
-  outputs = [
-    "$root_gen_dir/observatory/observatory_archive.cc",
-    "$root_gen_dir/observatory/observatory_archive.tar",
-  ]
+    outputs = [
+      "$root_gen_dir/observatory/${output_name}.cc",
+      "$root_gen_dir/observatory/${output_name}.tar",
+    ]
+  }
+}
+
+observatory_archive("embedded_archive_observatory") {
+  outer_namespace = "dart"
+  inner_namespace = "observatory"
 }
 
 source_set("embedded_observatory_archive") {
   deps = [
-    ":archive_observatory",
+    ":embedded_archive_observatory",
   ]
 
   sources = [
-    rebase_path("$root_gen_dir/observatory/observatory_archive.cc"),
+    rebase_path("$root_gen_dir/observatory/embedded_archive_observatory.cc"),
+  ]
+}
+
+observatory_archive("standalone_archive_observatory") {
+  outer_namespace = "dart"
+  inner_namespace = "bin"
+}
+
+source_set("standalone_observatory_archive") {
+  deps = [
+    ":standalone_archive_observatory",
+  ]
+
+  sources = [
+    rebase_path("$root_gen_dir/observatory/standalone_archive_observatory.cc"),
   ]
 }
diff --git a/runtime/vm/BUILD.gn b/runtime/vm/BUILD.gn
index 5f0a1ba8480..225afdf8892 100644
--- a/runtime/vm/BUILD.gn
+++ b/runtime/vm/BUILD.gn
@@ -25,7 +25,8 @@ config("libdart_vm_config") {
 
 
 static_library("libdart_platform") {
-  configs += ["..:dart_config", "..:dart_product_config"]
+  configs += ["..:dart_config",
+              "..:dart_maybe_product_config"]
   public_configs = [":libdart_vm_config"]
 
   platform_headers_gypi =
@@ -59,7 +60,20 @@ vm_sources_list = exec_script("../../tools/gypi_to_gn.py",
 
 static_library("libdart_vm") {
   configs += ["..:dart_config",
-              "..:dart_product_config",
+              "..:dart_maybe_product_config",
+              "..:dart_maybe_precompiled_runtime_config"]
+  public_configs = [":libdart_vm_config"]
+  set_sources_assignment_filter(["*_test.cc", "*_test.h"])
+  sources = vm_sources_list.sources
+  include_dirs = [
+    "..",
+  ]
+}
+
+
+static_library("libdart_vm_precompiled_runtime") {
+  configs += ["..:dart_config",
+              "..:dart_maybe_product_config",
               "..:dart_precompiled_runtime_config"]
   public_configs = [":libdart_vm_config"]
   set_sources_assignment_filter(["*_test.cc", "*_test.h"])
@@ -72,10 +86,24 @@ static_library("libdart_vm") {
 
 static_library("libdart_vm_nosnapshot") {
   configs += ["..:dart_config",
-              "..:dart_product_config",
-              "..:dart_precompiled_runtime_config"]
+              "..:dart_maybe_product_config",
+              "..:dart_maybe_precompiled_runtime_config",
+              "..:dart_no_snapshot_config",]
+  public_configs = [":libdart_vm_config"]
+  set_sources_assignment_filter(["*_test.cc", "*_test.h"])
+  sources = vm_sources_list.sources
+  include_dirs = [
+    "..",
+  ]
+}
+
+
+static_library("libdart_vm_nosnapshot_precompiled_runtime") {
+  configs += ["..:dart_config",
+              "..:dart_maybe_product_config",
+              "..:dart_precompiled_runtime_config",
+              "..:dart_no_snapshot_config",]
   public_configs = [":libdart_vm_config"]
-  defines = [ "DART_NO_SNAPSHOT" ]
   set_sources_assignment_filter(["*_test.cc", "*_test.h"])
   sources = vm_sources_list.sources
   include_dirs = [
@@ -86,10 +114,10 @@ static_library("libdart_vm_nosnapshot") {
 
 static_library("libdart_vm_nosnapshot_with_precompiler") {
   configs += ["..:dart_config",
-              "..:dart_product_config",
-              "..:dart_precompiler_config"]
+              "..:dart_maybe_product_config",
+              "..:dart_precompiler_config",
+              "..:dart_no_snapshot_config",]
   public_configs = [":libdart_vm_config"]
-  defines = [ "DART_NO_SNAPSHOT" ]
   set_sources_assignment_filter(["*_test.cc", "*_test.h"])
   sources = vm_sources_list.sources
   include_dirs = [
@@ -190,7 +218,17 @@ template("generate_core_libraries") {
 
   static_library("libdart_lib_nosnapshot") {
     configs += ["..:dart_config",
-                "..:dart_product_config",
+                "..:dart_maybe_product_config",
+                "..:dart_maybe_precompiled_runtime_config"]
+    deps = libdeps
+    sources = libsources + ["bootstrap.cc"] + liboutputs
+    include_dirs = [
+      "..",
+    ]
+  }
+  static_library("libdart_lib_nosnapshot_precompiled_runtime") {
+    configs += ["..:dart_config",
+                "..:dart_maybe_product_config",
                 "..:dart_precompiled_runtime_config"]
     deps = libdeps
     sources = libsources + ["bootstrap.cc"] + liboutputs
@@ -200,7 +238,7 @@ template("generate_core_libraries") {
   }
   static_library("libdart_lib_nosnapshot_with_precompiler") {
     configs += ["..:dart_config",
-                "..:dart_product_config",
+                "..:dart_maybe_product_config",
                 "..:dart_precompiler_config" ]
     deps = libdeps
     sources = libsources + [ "bootstrap.cc"] + liboutputs
@@ -210,7 +248,16 @@ template("generate_core_libraries") {
   }
   static_library("libdart_lib") {
     configs += ["..:dart_config",
-                "..:dart_product_config",
+                "..:dart_maybe_product_config",
+                "..:dart_maybe_precompiled_runtime_config"]
+    sources = libsources + [ "bootstrap_nocore.cc"]
+    include_dirs = [
+      "..",
+    ]
+  }
+  static_library("libdart_lib_precompiled_runtime") {
+    configs += ["..:dart_config",
+                "..:dart_maybe_product_config",
                 "..:dart_precompiled_runtime_config"]
     sources = libsources + [ "bootstrap_nocore.cc"]
     include_dirs = [
diff --git a/tools/clang/scripts/update.py b/tools/clang/scripts/update.py
new file mode 100755
index 00000000000..55b64eeffa9
--- /dev/null
+++ b/tools/clang/scripts/update.py
@@ -0,0 +1,771 @@
+#!/usr/bin/env python
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Windows can't run .sh files, so this is a Python implementation of
+update.sh. This script should replace update.sh on all platforms eventually."""
+
+import argparse
+import contextlib
+import cStringIO
+import glob
+import os
+import pipes
+import re
+import shutil
+import subprocess
+import stat
+import sys
+import tarfile
+import time
+import urllib2
+import zipfile
+
+# Do NOT CHANGE this if you don't know what you're doing -- see
+# https://code.google.com/p/chromium/wiki/UpdatingClang
+# Reverting problematic clang rolls is safe, though.
+# Note: this revision is only used for Windows. Other platforms use update.sh.
+# TODO(thakis): Use the same revision on Windows and non-Windows.
+# TODO(thakis): Remove update.sh, use update.py everywhere.
+LLVM_WIN_REVISION = '242415'
+
+use_head_revision = 'LLVM_FORCE_HEAD_REVISION' in os.environ
+if use_head_revision:
+  LLVM_WIN_REVISION = 'HEAD'
+
+# This is incremented when pushing a new build of Clang at the same revision.
+CLANG_SUB_REVISION=1
+
+PACKAGE_VERSION = "%s-%s" % (LLVM_WIN_REVISION, CLANG_SUB_REVISION)
+
+# Path constants. (All of these should be absolute paths.)
+THIS_DIR = os.path.abspath(os.path.dirname(__file__))
+CHROMIUM_DIR = os.path.abspath(os.path.join(THIS_DIR, '..', '..', '..'))
+THIRD_PARTY_DIR = os.path.join(CHROMIUM_DIR, 'third_party')
+LLVM_DIR = os.path.join(THIRD_PARTY_DIR, 'llvm')
+LLVM_BOOTSTRAP_DIR = os.path.join(THIRD_PARTY_DIR, 'llvm-bootstrap')
+LLVM_BOOTSTRAP_INSTALL_DIR = os.path.join(THIRD_PARTY_DIR,
+                                          'llvm-bootstrap-install')
+CHROME_TOOLS_SHIM_DIR = os.path.join(LLVM_DIR, 'tools', 'chrometools')
+LLVM_BUILD_DIR = os.path.join(CHROMIUM_DIR, 'third_party', 'llvm-build',
+                              'Release+Asserts')
+COMPILER_RT_BUILD_DIR = os.path.join(LLVM_BUILD_DIR, '32bit-compiler-rt')
+CLANG_DIR = os.path.join(LLVM_DIR, 'tools', 'clang')
+LLD_DIR = os.path.join(LLVM_DIR, 'tools', 'lld')
+COMPILER_RT_DIR = os.path.join(LLVM_DIR, 'projects', 'compiler-rt')
+LIBCXX_DIR = os.path.join(LLVM_DIR, 'projects', 'libcxx')
+LIBCXXABI_DIR = os.path.join(LLVM_DIR, 'projects', 'libcxxabi')
+LLVM_BUILD_TOOLS_DIR = os.path.abspath(
+    os.path.join(LLVM_DIR, '..', 'llvm-build-tools'))
+STAMP_FILE = os.path.join(LLVM_DIR, '..', 'llvm-build', 'cr_build_revision')
+BINUTILS_DIR = os.path.join(THIRD_PARTY_DIR, 'binutils')
+VERSION = '3.8.0'
+
+# URL for pre-built binaries.
+CDS_URL = 'https://commondatastorage.googleapis.com/chromium-browser-clang'
+
+LLVM_REPO_URL='https://llvm.org/svn/llvm-project'
+if 'LLVM_REPO_URL' in os.environ:
+  LLVM_REPO_URL = os.environ['LLVM_REPO_URL']
+
+
+def DownloadUrl(url, output_file):
+  """Download url into output_file."""
+  CHUNK_SIZE = 4096
+  TOTAL_DOTS = 10
+  sys.stdout.write('Downloading %s ' % url)
+  sys.stdout.flush()
+  response = urllib2.urlopen(url)
+  total_size = int(response.info().getheader('Content-Length').strip())
+  bytes_done = 0
+  dots_printed = 0
+  while True:
+    chunk = response.read(CHUNK_SIZE)
+    if not chunk:
+      break
+    output_file.write(chunk)
+    bytes_done += len(chunk)
+    num_dots = TOTAL_DOTS * bytes_done / total_size
+    sys.stdout.write('.' * (num_dots - dots_printed))
+    sys.stdout.flush()
+    dots_printed = num_dots
+  print ' Done.'
+
+
+def ReadStampFile():
+  """Return the contents of the stamp file, or '' if it doesn't exist."""
+  try:
+    with open(STAMP_FILE, 'r') as f:
+      return f.read()
+  except IOError:
+    return ''
+
+
+def WriteStampFile(s):
+  """Write s to the stamp file."""
+  if not os.path.exists(os.path.dirname(STAMP_FILE)):
+    os.makedirs(os.path.dirname(STAMP_FILE))
+  with open(STAMP_FILE, 'w') as f:
+    f.write(s)
+
+
+def GetSvnRevision(svn_repo):
+  """Returns current revision of the svn repo at svn_repo."""
+  svn_info = subprocess.check_output('svn info ' + svn_repo, shell=True)
+  m = re.search(r'Revision: (\d+)', svn_info)
+  return m.group(1)
+
+
+def RmTree(dir):
+  """Delete dir."""
+  def ChmodAndRetry(func, path, _):
+    # Subversion can leave read-only files around.
+    if not os.access(path, os.W_OK):
+      os.chmod(path, stat.S_IWUSR)
+      return func(path)
+    raise
+
+  shutil.rmtree(dir, onerror=ChmodAndRetry)
+
+
+def RunCommand(command, msvc_arch=None, env=None, fail_hard=True):
+  """Run command and return success (True) or failure; or if fail_hard is
+     True, exit on failure.  If msvc_arch is set, runs the command in a
+     shell with the msvc tools for that architecture."""
+
+  if msvc_arch and sys.platform == 'win32':
+    command = GetVSVersion().SetupScript(msvc_arch) + ['&&'] + command
+
+  # https://docs.python.org/2/library/subprocess.html:
+  # "On Unix with shell=True [...] if args is a sequence, the first item
+  # specifies the command string, and any additional items will be treated as
+  # additional arguments to the shell itself.  That is to say, Popen does the
+  # equivalent of:
+  #   Popen(['/bin/sh', '-c', args[0], args[1], ...])"
+  #
+  # We want to pass additional arguments to command[0], not to the shell,
+  # so manually join everything into a single string.
+  # Annoyingly, for "svn co url c:\path", pipes.quote() thinks that it should
+  # quote c:\path but svn can't handle quoted paths on Windows.  Since on
+  # Windows follow-on args are passed to args[0] instead of the shell, don't
+  # do the single-string transformation there.
+  if sys.platform != 'win32':
+    command = ' '.join([pipes.quote(c) for c in command])
+  print 'Running', command
+  if subprocess.call(command, env=env, shell=True) == 0:
+    return True
+  print 'Failed.'
+  if fail_hard:
+    sys.exit(1)
+  return False
+
+
+def CopyFile(src, dst):
+  """Copy a file from src to dst."""
+  shutil.copy(src, dst)
+  print "Copying %s to %s" % (src, dst)
+
+
+def CopyDirectoryContents(src, dst, filename_filter=None):
+  """Copy the files from directory src to dst
+  with an optional filename filter."""
+  if not os.path.exists(dst):
+    os.makedirs(dst)
+  for root, _, files in os.walk(src):
+    for f in files:
+      if filename_filter and not re.match(filename_filter, f):
+        continue
+      CopyFile(os.path.join(root, f), dst)
+
+
+def Checkout(name, url, dir):
+  """Checkout the SVN module at url into dir. Use name for the log message."""
+  print "Checking out %s r%s into '%s'" % (name, LLVM_WIN_REVISION, dir)
+
+  command = ['svn', 'checkout', '--force', url + '@' + LLVM_WIN_REVISION, dir]
+  if RunCommand(command, fail_hard=False):
+    return
+
+  if os.path.isdir(dir):
+    print "Removing %s." % (dir)
+    RmTree(dir)
+
+  print "Retrying."
+  RunCommand(command)
+
+
+def RevertPreviouslyPatchedFiles():
+  print 'Reverting previously patched files'
+  files = [
+    '%(clang)s/test/Index/crash-recovery-modules.m',
+    '%(clang)s/unittests/libclang/LibclangTest.cpp',
+    '%(compiler_rt)s/lib/asan/asan_rtl.cc',
+    '%(compiler_rt)s/test/asan/TestCases/Linux/new_array_cookie_test.cc',
+    '%(llvm)s/test/DebugInfo/gmlt.ll',
+    '%(llvm)s/lib/CodeGen/SpillPlacement.cpp',
+    '%(llvm)s/lib/CodeGen/SpillPlacement.h',
+    '%(llvm)s/lib/Transforms/Instrumentation/MemorySanitizer.cpp',
+    '%(clang)s/test/Driver/env.c',
+    '%(clang)s/lib/Frontend/InitPreprocessor.cpp',
+    '%(clang)s/test/Frontend/exceptions.c',
+    '%(clang)s/test/Preprocessor/predefined-exceptions.m',
+    '%(llvm)s/test/Bindings/Go/go.test',
+    '%(clang)s/lib/Parse/ParseExpr.cpp',
+    '%(clang)s/lib/Parse/ParseTemplate.cpp',
+    '%(clang)s/lib/Sema/SemaDeclCXX.cpp',
+    '%(clang)s/lib/Sema/SemaExprCXX.cpp',
+    '%(clang)s/test/SemaCXX/default2.cpp',
+    '%(clang)s/test/SemaCXX/typo-correction-delayed.cpp',
+    '%(compiler_rt)s/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc',
+    '%(compiler_rt)s/test/tsan/signal_segv_handler.cc',
+    '%(compiler_rt)s/lib/sanitizer_common/sanitizer_coverage_libcdep.cc',
+    '%(compiler_rt)s/cmake/config-ix.cmake',
+    '%(compiler_rt)s/CMakeLists.txt',
+    '%(compiler_rt)s/lib/ubsan/ubsan_platform.h',
+    ]
+  for f in files:
+    f = f % {
+        'clang': CLANG_DIR,
+        'compiler_rt': COMPILER_RT_DIR,
+        'llvm': LLVM_DIR,
+        }
+    if os.path.exists(f):
+      os.remove(f)  # For unversioned files.
+      RunCommand(['svn', 'revert', f])
+
+
+def ApplyLocalPatches():
+  # There's no patch program on Windows by default.  We don't need patches on
+  # Windows yet, and maybe this not working on Windows will motivate us to
+  # remove patches over time.
+  assert sys.platform != 'win32'
+
+  # Apply patch for tests failing with --disable-pthreads (llvm.org/PR11974)
+  clang_patches = [ r"""\
+--- test/Index/crash-recovery-modules.m	(revision 202554)
++++ test/Index/crash-recovery-modules.m	(working copy)
+@@ -12,6 +12,8 @@
+ 
+ // REQUIRES: crash-recovery
+ // REQUIRES: shell
++// XFAIL: *
++//    (PR11974)
+ 
+ @import Crash;
+""", r"""\
+--- unittests/libclang/LibclangTest.cpp (revision 215949)
++++ unittests/libclang/LibclangTest.cpp (working copy)
+@@ -431,7 +431,7 @@
+   EXPECT_EQ(0U, clang_getNumDiagnostics(ClangTU));
+ }
+
+-TEST_F(LibclangReparseTest, ReparseWithModule) {
++TEST_F(LibclangReparseTest, DISABLED_ReparseWithModule) {
+   const char *HeaderTop = "#ifndef H\n#define H\nstruct Foo { int bar;";
+   const char *HeaderBottom = "\n};\n#endif\n";
+   const char *MFile = "#include \"HeaderFile.h\"\nint main() {"
+"""
+      ]
+
+  # This Go bindings test doesn't work after bootstrap on Linux, PR21552.
+  llvm_patches = [ r"""\
+--- test/Bindings/Go/go.test    (revision 223109)
++++ test/Bindings/Go/go.test    (working copy)
+@@ -1,3 +1,3 @@
+-; RUN: llvm-go test llvm.org/llvm/bindings/go/llvm
++; RUN: true
+ 
+ ; REQUIRES: shell
+"""
+      ]
+
+  # The UBSan run-time, which is now bundled with the ASan run-time, doesn't
+  # work on Mac OS X 10.8 (PR23539).
+  compiler_rt_patches = [ r"""\
+--- CMakeLists.txt	(revision 241602)
++++ CMakeLists.txt	(working copy)
+@@ -305,6 +305,7 @@
+       list(APPEND SANITIZER_COMMON_SUPPORTED_OS iossim)
+     endif()
+   endif()
++  set(SANITIZER_MIN_OSX_VERSION "10.7")
+   if(SANITIZER_MIN_OSX_VERSION VERSION_LESS "10.7")
+     message(FATAL_ERROR "Too old OS X version: ${SANITIZER_MIN_OSX_VERSION}")
+   endif()
+"""
+      ]
+
+  for path, patches in [(LLVM_DIR, llvm_patches),
+                        (CLANG_DIR, clang_patches),
+                        (COMPILER_RT_DIR, compiler_rt_patches)]:
+    print 'Applying patches in', path
+    for patch in patches:
+      print patch
+      p = subprocess.Popen( ['patch', '-p0', '-d', path], stdin=subprocess.PIPE)
+      (stdout, stderr) = p.communicate(input=patch)
+      if p.returncode != 0:
+        raise RuntimeError('stdout %s, stderr %s' % (stdout, stderr))
+
+
+def DeleteChromeToolsShim():
+  shutil.rmtree(CHROME_TOOLS_SHIM_DIR, ignore_errors=True)
+
+
+def CreateChromeToolsShim():
+  """Hooks the Chrome tools into the LLVM build.
+
+  Several Chrome tools have dependencies on LLVM/Clang libraries. The LLVM build
+  detects implicit tools in the tools subdirectory, so this helper install a
+  shim CMakeLists.txt that forwards to the real directory for the Chrome tools.
+
+  Note that the shim directory name intentionally has no - or _. The implicit
+  tool detection logic munges them in a weird way."""
+  assert not any(i in os.path.basename(CHROME_TOOLS_SHIM_DIR) for i in '-_')
+  os.mkdir(CHROME_TOOLS_SHIM_DIR)
+  with file(os.path.join(CHROME_TOOLS_SHIM_DIR, 'CMakeLists.txt'), 'w') as f:
+    f.write('# Automatically generated by tools/clang/scripts/update.py. ' +
+            'Do not edit.\n')
+    f.write('# Since tools/clang is located in another directory, use the \n')
+    f.write('# two arg version to specify where build artifacts go. CMake\n')
+    f.write('# disallows reuse of the same binary dir for multiple source\n')
+    f.write('# dirs, so the build artifacts need to go into a subdirectory.\n')
+    f.write('# dirs, so the build artifacts need to go into a subdirectory.\n')
+    f.write('if (CHROMIUM_TOOLS_SRC)\n')
+    f.write('  add_subdirectory(${CHROMIUM_TOOLS_SRC} ' +
+              '${CMAKE_CURRENT_BINARY_DIR}/a)\n')
+    f.write('endif (CHROMIUM_TOOLS_SRC)\n')
+
+
+def AddCMakeToPath():
+  """Download CMake and add it to PATH."""
+  if sys.platform == 'win32':
+    zip_name = 'cmake-3.2.2-win32-x86.zip'
+    cmake_dir = os.path.join(LLVM_BUILD_TOOLS_DIR,
+                             'cmake-3.2.2-win32-x86', 'bin')
+  else:
+    suffix = 'Darwin' if sys.platform == 'darwin' else 'Linux'
+    zip_name = 'cmake310_%s.tgz' % suffix
+    cmake_dir = os.path.join(LLVM_BUILD_TOOLS_DIR, 'cmake310', 'bin')
+  if not os.path.exists(cmake_dir):
+    if not os.path.exists(LLVM_BUILD_TOOLS_DIR):
+      os.makedirs(LLVM_BUILD_TOOLS_DIR)
+    # The cmake archive is smaller than 20 MB, small enough to keep in memory:
+    with contextlib.closing(cStringIO.StringIO()) as f:
+      DownloadUrl(CDS_URL + '/tools/' + zip_name, f)
+      f.seek(0)
+      if zip_name.endswith('.zip'):
+        zipfile.ZipFile(f).extractall(path=LLVM_BUILD_TOOLS_DIR)
+      else:
+        tarfile.open(mode='r:gz', fileobj=f).extractall(path=
+            LLVM_BUILD_TOOLS_DIR)
+  os.environ['PATH'] = cmake_dir + os.pathsep + os.environ.get('PATH', '')
+
+vs_version = None
+def GetVSVersion():
+  global vs_version
+  if vs_version:
+    return vs_version
+
+  # Try using the toolchain in depot_tools.
+  # This sets environment variables used by SelectVisualStudioVersion below.
+  sys.path.append(os.path.join(CHROMIUM_DIR, 'build'))
+  import vs_toolchain
+  vs_toolchain.SetEnvironmentAndGetRuntimeDllDirs()
+
+  # Use gyp to find the MSVS installation, either in depot_tools as per above,
+  # or a system-wide installation otherwise.
+  sys.path.append(os.path.join(CHROMIUM_DIR, 'tools', 'gyp', 'pylib'))
+  import gyp.MSVSVersion
+  vs_version = gyp.MSVSVersion.SelectVisualStudioVersion('2013')
+  return vs_version
+
+
+def UpdateClang(args):
+  print 'Updating Clang to %s...' % PACKAGE_VERSION
+  if ReadStampFile() == PACKAGE_VERSION:
+    print 'Already up to date.'
+    return 0
+
+  # Reset the stamp file in case the build is unsuccessful.
+  WriteStampFile('')
+
+  if not args.force_local_build:
+    cds_file = "clang-%s.tgz" %  PACKAGE_VERSION
+    cds_full_url = CDS_URL + '/Win/' + cds_file
+
+    # Check if there's a prebuilt binary and if so just fetch that. That's
+    # faster, and goma relies on having matching binary hashes on client and
+    # server too.
+    print 'Trying to download prebuilt clang'
+
+    # clang packages are smaller than 50 MB, small enough to keep in memory.
+    with contextlib.closing(cStringIO.StringIO()) as f:
+      try:
+        DownloadUrl(cds_full_url, f)
+        f.seek(0)
+        tarfile.open(mode='r:gz', fileobj=f).extractall(path=LLVM_BUILD_DIR)
+        print 'clang %s unpacked' % PACKAGE_VERSION
+        # Download the gold plugin if requested to by an environment variable.
+        # This is used by the CFI ClusterFuzz bot.
+        if 'LLVM_DOWNLOAD_GOLD_PLUGIN' in os.environ:
+          RunCommand(['python', CHROMIUM_DIR+'/build/download_gold_plugin.py'])
+        WriteStampFile(PACKAGE_VERSION)
+        return 0
+      except urllib2.HTTPError:
+        print 'Did not find prebuilt clang %s, building locally' % cds_file
+
+  AddCMakeToPath()
+
+  RevertPreviouslyPatchedFiles()
+  DeleteChromeToolsShim()
+
+  Checkout('LLVM', LLVM_REPO_URL + '/llvm/trunk', LLVM_DIR)
+  Checkout('Clang', LLVM_REPO_URL + '/cfe/trunk', CLANG_DIR)
+  if sys.platform == 'win32':
+    Checkout('LLD', LLVM_REPO_URL + '/lld/trunk', LLD_DIR)
+  Checkout('compiler-rt', LLVM_REPO_URL + '/compiler-rt/trunk', COMPILER_RT_DIR)
+  if sys.platform == 'darwin':
+    # clang needs a libc++ checkout, else -stdlib=libc++ won't find includes
+    # (i.e. this is needed for bootstrap builds).
+    Checkout('libcxx', LLVM_REPO_URL + '/libcxx/trunk', LIBCXX_DIR)
+    # While we're bundling our own libc++ on OS X, we need to compile libc++abi
+    # into it too (since OS X 10.6 doesn't have libc++abi.dylib either).
+    Checkout('libcxxabi', LLVM_REPO_URL + '/libcxxabi/trunk', LIBCXXABI_DIR)
+
+  if args.with_patches and sys.platform != 'win32':
+    ApplyLocalPatches()
+
+  cc, cxx = None, None
+  cflags = cxxflags = ldflags = []
+
+  # LLVM uses C++11 starting in llvm 3.5. On Linux, this means libstdc++4.7+ is
+  # needed, on OS X it requires libc++. clang only automatically links to libc++
+  # when targeting OS X 10.9+, so add stdlib=libc++ explicitly so clang can run
+  # on OS X versions as old as 10.7.
+  # TODO(thakis): Some bots are still on 10.6 (nacl...), so for now bundle
+  # libc++.dylib.  Remove this once all bots are on 10.7+, then use
+  # -DLLVM_ENABLE_LIBCXX=ON and change deployment_target to 10.7.
+  deployment_target = ''
+
+  if sys.platform == 'darwin':
+    # When building on 10.9, /usr/include usually doesn't exist, and while
+    # Xcode's clang automatically sets a sysroot, self-built clangs don't.
+    cflags = ['-isysroot', subprocess.check_output(
+        ['xcrun', '--show-sdk-path']).rstrip()]
+    cxxflags = ['-stdlib=libc++', '-nostdinc++',
+                '-I' + os.path.join(LIBCXX_DIR, 'include')] + cflags
+    if args.bootstrap:
+      deployment_target = '10.6'
+
+  base_cmake_args = ['-GNinja',
+                     '-DCMAKE_BUILD_TYPE=Release',
+                     '-DLLVM_ENABLE_ASSERTIONS=ON',
+                     '-DLLVM_ENABLE_THREADS=OFF',
+                     ]
+
+  if args.bootstrap:
+    print 'Building bootstrap compiler'
+    if not os.path.exists(LLVM_BOOTSTRAP_DIR):
+      os.makedirs(LLVM_BOOTSTRAP_DIR)
+    os.chdir(LLVM_BOOTSTRAP_DIR)
+    bootstrap_args = base_cmake_args + [
+        '-DLLVM_TARGETS_TO_BUILD=host',
+        '-DCMAKE_INSTALL_PREFIX=' + LLVM_BOOTSTRAP_INSTALL_DIR,
+        '-DCMAKE_C_FLAGS=' + ' '.join(cflags),
+        '-DCMAKE_CXX_FLAGS=' + ' '.join(cxxflags),
+        ]
+    if cc is not None:  bootstrap_args.append('-DCMAKE_C_COMPILER=' + cc)
+    if cxx is not None: bootstrap_args.append('-DCMAKE_CXX_COMPILER=' + cxx)
+    RunCommand(['cmake'] + bootstrap_args + [LLVM_DIR], msvc_arch='x64')
+    RunCommand(['ninja'], msvc_arch='x64')
+    if args.run_tests:
+      RunCommand(['ninja', 'check-all'], msvc_arch='x64')
+    RunCommand(['ninja', 'install'], msvc_arch='x64')
+
+    if sys.platform == 'win32':
+      cc = os.path.join(LLVM_BOOTSTRAP_INSTALL_DIR, 'bin', 'clang-cl.exe')
+      cxx = os.path.join(LLVM_BOOTSTRAP_INSTALL_DIR, 'bin', 'clang-cl.exe')
+      # CMake has a hard time with backslashes in compiler paths:
+      # https://stackoverflow.com/questions/13050827
+      cc = cc.replace('\\', '/')
+      cxx = cxx.replace('\\', '/')
+    else:
+      cc = os.path.join(LLVM_BOOTSTRAP_INSTALL_DIR, 'bin', 'clang')
+      cxx = os.path.join(LLVM_BOOTSTRAP_INSTALL_DIR, 'bin', 'clang++')
+    print 'Building final compiler'
+
+  if sys.platform == 'darwin':
+    # Build libc++.dylib while some bots are still on OS X 10.6.
+    libcxxbuild = os.path.join(LLVM_BUILD_DIR, 'libcxxbuild')
+    if os.path.isdir(libcxxbuild):
+      RmTree(libcxxbuild)
+    libcxxflags = ['-O3', '-std=c++11', '-fstrict-aliasing']
+
+    # libcxx and libcxxabi both have a file stdexcept.cpp, so put their .o files
+    # into different subdirectories.
+    os.makedirs(os.path.join(libcxxbuild, 'libcxx'))
+    os.chdir(os.path.join(libcxxbuild, 'libcxx'))
+    RunCommand(['c++', '-c'] + cxxflags + libcxxflags +
+                glob.glob(os.path.join(LIBCXX_DIR, 'src', '*.cpp')))
+
+    os.makedirs(os.path.join(libcxxbuild, 'libcxxabi'))
+    os.chdir(os.path.join(libcxxbuild, 'libcxxabi'))
+    RunCommand(['c++', '-c'] + cxxflags + libcxxflags +
+               glob.glob(os.path.join(LIBCXXABI_DIR, 'src', '*.cpp')) +
+               ['-I' + os.path.join(LIBCXXABI_DIR, 'include')])
+
+    os.chdir(libcxxbuild)
+    libdir = os.path.join(LIBCXX_DIR, 'lib')
+    RunCommand(['cc'] + glob.glob('libcxx/*.o') + glob.glob('libcxxabi/*.o') +
+        ['-o', 'libc++.1.dylib', '-dynamiclib', '-nodefaultlibs',
+         '-current_version', '1', '-compatibility_version', '1', '-lSystem',
+         '-install_name', '@executable_path/libc++.dylib',
+         '-Wl,-unexported_symbols_list,' + libdir + '/libc++unexp.exp',
+         '-Wl,-force_symbols_not_weak_list,' + libdir + '/notweak.exp',
+         '-Wl,-force_symbols_weak_list,' + libdir + '/weak.exp'])
+    if os.path.exists('libc++.dylib'):
+      os.remove('libc++.dylib')
+    os.symlink('libc++.1.dylib', 'libc++.dylib')
+    ldflags += ['-stdlib=libc++', '-L' + libcxxbuild]
+
+    if args.bootstrap:
+      # Now that the libc++ headers have been installed and libc++.dylib is
+      # built, delete the libc++ checkout again so that it's not part of the
+      # main build below -- the libc++(abi) tests don't pass on OS X in
+      # bootstrap builds (http://llvm.org/PR24068)
+      RmTree(LIBCXX_DIR)
+      RmTree(LIBCXXABI_DIR)
+      cxxflags = ['-stdlib=libc++', '-nostdinc++',
+                  '-I' + os.path.join(LLVM_BOOTSTRAP_INSTALL_DIR,
+                                      'include/c++/v1')
+                  ] + cflags
+
+  # Build clang.
+  binutils_incdir = ''
+  if sys.platform.startswith('linux'):
+    binutils_incdir = os.path.join(BINUTILS_DIR, 'Linux_x64/Release/include')
+
+  # If building at head, define a macro that plugins can use for #ifdefing
+  # out code that builds at head, but not at LLVM_WIN_REVISION or vice versa.
+  if use_head_revision:
+    cflags += ['-DLLVM_FORCE_HEAD_REVISION']
+    cxxflags += ['-DLLVM_FORCE_HEAD_REVISION']
+
+  CreateChromeToolsShim()
+
+  deployment_env = None
+  if deployment_target:
+    deployment_env = os.environ.copy()
+    deployment_env['MACOSX_DEPLOYMENT_TARGET'] = deployment_target
+
+  cmake_args = base_cmake_args + [
+      '-DLLVM_BINUTILS_INCDIR=' + binutils_incdir,
+      '-DCMAKE_C_FLAGS=' + ' '.join(cflags),
+      '-DCMAKE_CXX_FLAGS=' + ' '.join(cxxflags),
+      '-DCMAKE_EXE_LINKER_FLAGS=' + ' '.join(ldflags),
+      '-DCMAKE_SHARED_LINKER_FLAGS=' + ' '.join(ldflags),
+      '-DCMAKE_MODULE_LINKER_FLAGS=' + ' '.join(ldflags),
+      '-DCMAKE_INSTALL_PREFIX=' + LLVM_BUILD_DIR,
+      '-DCHROMIUM_TOOLS_SRC=%s' % os.path.join(CHROMIUM_DIR, 'tools', 'clang'),
+      '-DCHROMIUM_TOOLS=%s' % ';'.join(args.tools)]
+  # TODO(thakis): Unconditionally append this to base_cmake_args instead once
+  # compiler-rt can build with clang-cl on Windows (http://llvm.org/PR23698)
+  cc_args = base_cmake_args if sys.platform != 'win32' else cmake_args
+  if cc is not None:  cc_args.append('-DCMAKE_C_COMPILER=' + cc)
+  if cxx is not None: cc_args.append('-DCMAKE_CXX_COMPILER=' + cxx)
+
+  if not os.path.exists(LLVM_BUILD_DIR):
+    os.makedirs(LLVM_BUILD_DIR)
+  os.chdir(LLVM_BUILD_DIR)
+  RunCommand(['cmake'] + cmake_args + [LLVM_DIR],
+             msvc_arch='x64', env=deployment_env)
+  RunCommand(['ninja'], msvc_arch='x64')
+
+  if args.tools:
+    # If any Chromium tools were built, install those now.
+    RunCommand(['ninja', 'cr-install'], msvc_arch='x64')
+
+  if sys.platform == 'darwin':
+    CopyFile(os.path.join(LLVM_BUILD_DIR, 'libc++.1.dylib'),
+             os.path.join(LLVM_BUILD_DIR, 'bin'))
+    # See http://crbug.com/256342
+    RunCommand(['strip', '-x', os.path.join(LLVM_BUILD_DIR, 'bin', 'clang')])
+  elif sys.platform.startswith('linux'):
+    RunCommand(['strip', os.path.join(LLVM_BUILD_DIR, 'bin', 'clang')])
+
+  # Do an x86 build of compiler-rt to get the 32-bit ASan run-time.
+  # TODO(hans): Remove once the regular build above produces this.
+  if not os.path.exists(COMPILER_RT_BUILD_DIR):
+    os.makedirs(COMPILER_RT_BUILD_DIR)
+  os.chdir(COMPILER_RT_BUILD_DIR)
+  # TODO(thakis): Add this once compiler-rt can build with clang-cl (see
+  # above).
+  #if args.bootstrap and sys.platform == 'win32':
+    # The bootstrap compiler produces 64-bit binaries by default.
+    #cflags += ['-m32']
+    #cxxflags += ['-m32']
+  compiler_rt_args = base_cmake_args + [
+      '-DCMAKE_C_FLAGS=' + ' '.join(cflags),
+      '-DCMAKE_CXX_FLAGS=' + ' '.join(cxxflags)]
+  if sys.platform != 'win32':
+    compiler_rt_args += ['-DLLVM_CONFIG_PATH=' +
+                         os.path.join(LLVM_BUILD_DIR, 'bin', 'llvm-config')]
+  RunCommand(['cmake'] + compiler_rt_args + [LLVM_DIR],
+              msvc_arch='x86', env=deployment_env)
+  RunCommand(['ninja', 'compiler-rt'], msvc_arch='x86')
+
+  # TODO(hans): Make this (and the .gypi and .isolate files) version number
+  # independent.
+  if sys.platform == 'win32':
+    platform = 'windows'
+  elif sys.platform == 'darwin':
+    platform = 'darwin'
+  else:
+    assert sys.platform.startswith('linux')
+    platform = 'linux'
+  asan_rt_lib_src_dir = os.path.join(COMPILER_RT_BUILD_DIR, 'lib', 'clang',
+                                     VERSION, 'lib', platform)
+  asan_rt_lib_dst_dir = os.path.join(LLVM_BUILD_DIR, 'lib', 'clang',
+                                     VERSION, 'lib', platform)
+  CopyDirectoryContents(asan_rt_lib_src_dir, asan_rt_lib_dst_dir,
+                        r'^.*-i386\.lib$')
+  CopyDirectoryContents(asan_rt_lib_src_dir, asan_rt_lib_dst_dir,
+                        r'^.*-i386\.dll$')
+
+  CopyFile(os.path.join(asan_rt_lib_src_dir, '..', '..', 'asan_blacklist.txt'),
+           os.path.join(asan_rt_lib_dst_dir, '..', '..'))
+
+  if sys.platform == 'win32':
+    # Make an extra copy of the sanitizer headers, to be put on the include path
+    # of the fallback compiler.
+    sanitizer_include_dir = os.path.join(LLVM_BUILD_DIR, 'lib', 'clang',
+                                         VERSION, 'include', 'sanitizer')
+    aux_sanitizer_include_dir = os.path.join(LLVM_BUILD_DIR, 'lib', 'clang',
+                                             VERSION, 'include_sanitizer',
+                                             'sanitizer')
+    if not os.path.exists(aux_sanitizer_include_dir):
+      os.makedirs(aux_sanitizer_include_dir)
+    for _, _, files in os.walk(sanitizer_include_dir):
+      for f in files:
+        CopyFile(os.path.join(sanitizer_include_dir, f),
+                 aux_sanitizer_include_dir)
+
+  # Run tests.
+  if args.run_tests or use_head_revision:
+    os.chdir(LLVM_BUILD_DIR)
+    RunCommand(GetVSVersion().SetupScript('x64') +
+               ['&&', 'ninja', 'cr-check-all'])
+  if args.run_tests:
+    os.chdir(LLVM_BUILD_DIR)
+    RunCommand(GetVSVersion().SetupScript('x64') +
+               ['&&', 'ninja', 'check-all'])
+
+  WriteStampFile(PACKAGE_VERSION)
+  print 'Clang update was successful.'
+  return 0
+
+
+def main():
+  if not sys.platform in ['win32', 'cygwin']:
+    # For non-Windows, fall back to update.sh.
+    # TODO(hans): Make update.py replace update.sh completely.
+
+    # This script is called by gclient. gclient opens its hooks subprocesses
+    # with (stdout=subprocess.PIPE, stderr=subprocess.STDOUT) and then does
+    # custom output processing that breaks printing '\r' characters for
+    # single-line updating status messages as printed by curl and wget.
+    # Work around this by setting stderr of the update.sh process to stdin (!):
+    # gclient doesn't redirect stdin, and while stdin itself is read-only, a
+    # dup()ed sys.stdin is writable, try
+    #   fd2 = os.dup(sys.stdin.fileno()); os.write(fd2, 'hi')
+    # TODO: Fix gclient instead, http://crbug.com/95350
+    if '--no-stdin-hack' in sys.argv:
+      sys.argv.remove('--no-stdin-hack')
+      stderr = None
+    else:
+      try:
+        stderr = os.fdopen(os.dup(sys.stdin.fileno()))
+      except:
+        stderr = sys.stderr
+    return subprocess.call(
+        [os.path.join(os.path.dirname(__file__), 'update.sh')] + sys.argv[1:],
+        stderr=stderr)
+
+  parser = argparse.ArgumentParser(description='Build Clang.')
+  parser.add_argument('--bootstrap', action='store_true',
+                      help='first build clang with CC, then with itself.')
+  parser.add_argument('--if-needed', action='store_true',
+                      help="run only if the script thinks clang is needed")
+  parser.add_argument('--force-local-build', action='store_true',
+                      help="don't try to download prebuild binaries")
+  parser.add_argument('--print-revision', action='store_true',
+                      help='print current clang revision and exit.')
+  parser.add_argument('--print-clang-version', action='store_true',
+                      help='print current clang version (e.g. x.y.z) and exit.')
+  parser.add_argument('--run-tests', action='store_true',
+                      help='run tests after building; only for local builds')
+  parser.add_argument('--tools', nargs='*',
+                      help='select which chrome tools to build',
+                      default=['plugins', 'blink_gc_plugin'])
+  parser.add_argument('--without-patches', action='store_false',
+                      help="don't apply patches (default)", dest='with_patches',
+                      default=True)
+
+  # For now, these flags are only used for the non-Windows flow, but argparser
+  # gets mad if it sees a flag it doesn't recognize.
+  parser.add_argument('--no-stdin-hack', action='store_true')
+
+  args = parser.parse_args()
+
+  if args.if_needed:
+    is_clang_required = False
+    # clang is always used on Mac and Linux.
+    if sys.platform == 'darwin' or sys.platform.startswith('linux'):
+      is_clang_required = True
+    # clang requested via $GYP_DEFINES.
+    if re.search(r'\b(clang|asan|lsan|msan|tsan)=1',
+                 os.environ.get('GYP_DEFINES', '')):
+      is_clang_required = True
+    # clang previously downloaded, keep it up-to-date.
+    # If you don't want this, delete third_party/llvm-build on your machine.
+    if os.path.isdir(LLVM_BUILD_DIR):
+      is_clang_required = True
+    if not is_clang_required:
+      return 0
+    if re.search(r'\b(make_clang_dir)=', os.environ.get('GYP_DEFINES', '')):
+      print 'Skipping Clang update (make_clang_dir= was set in GYP_DEFINES).'
+      return 0
+
+  global LLVM_WIN_REVISION, PACKAGE_VERSION
+  if args.print_revision:
+    if use_head_revision:
+      print GetSvnRevision(LLVM_DIR)
+    else:
+      print PACKAGE_VERSION
+    return 0
+
+  if args.print_clang_version:
+    sys.stdout.write(VERSION)
+    return 0
+
+  # Don't buffer stdout, so that print statements are immediately flushed.
+  # Do this only after --print-revision has been handled, else we'll get
+  # an error message when this script is run from gn for some reason.
+  sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)
+
+  if use_head_revision:
+    # Use a real revision number rather than HEAD to make sure that the stamp
+    # file logic works.
+    LLVM_WIN_REVISION = GetSvnRevision(LLVM_REPO_URL)
+    PACKAGE_VERSION = LLVM_WIN_REVISION + '-0'
+
+    args.force_local_build = True
+    # Skip local patches when using HEAD: they probably don't apply anymore.
+    args.with_patches = False
+
+  return UpdateClang(args)
+
+
+if __name__ == '__main__':
+  sys.exit(main())
diff --git a/tools/clang/scripts/update.sh b/tools/clang/scripts/update.sh
new file mode 100755
index 00000000000..d85deae23c3
--- /dev/null
+++ b/tools/clang/scripts/update.sh
@@ -0,0 +1,724 @@
+#!/usr/bin/env bash
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This script will check out llvm and clang into third_party/llvm and build it.
+
+# Do NOT CHANGE this if you don't know what you're doing -- see
+# https://code.google.com/p/chromium/wiki/UpdatingClang
+# Reverting problematic clang rolls is safe, though.
+CLANG_REVISION=241602
+
+# This is incremented when pushing a new build of Clang at the same revision.
+CLANG_SUB_REVISION=3
+
+PACKAGE_VERSION="${CLANG_REVISION}-${CLANG_SUB_REVISION}"
+
+THIS_DIR="$(dirname "${0}")"
+LLVM_DIR="${THIS_DIR}/../../../third_party/llvm"
+LLVM_BUILD_DIR="${LLVM_DIR}/../llvm-build/Release+Asserts"
+COMPILER_RT_BUILD_DIR="${LLVM_DIR}/../llvm-build/compiler-rt"
+LLVM_BOOTSTRAP_DIR="${LLVM_DIR}/../llvm-bootstrap"
+LLVM_BOOTSTRAP_INSTALL_DIR="${LLVM_DIR}/../llvm-bootstrap-install"
+CLANG_DIR="${LLVM_DIR}/tools/clang"
+COMPILER_RT_DIR="${LLVM_DIR}/compiler-rt"
+LIBCXX_DIR="${LLVM_DIR}/projects/libcxx"
+LIBCXXABI_DIR="${LLVM_DIR}/projects/libcxxabi"
+ANDROID_NDK_DIR="${THIS_DIR}/../../../third_party/android_tools/ndk"
+STAMP_FILE="${LLVM_DIR}/../llvm-build/cr_build_revision"
+CHROMIUM_TOOLS_DIR="${THIS_DIR}/.."
+BINUTILS_DIR="${THIS_DIR}/../../../third_party/binutils"
+
+ABS_CHROMIUM_TOOLS_DIR="${PWD}/${CHROMIUM_TOOLS_DIR}"
+ABS_LIBCXX_DIR="${PWD}/${LIBCXX_DIR}"
+ABS_LIBCXXABI_DIR="${PWD}/${LIBCXXABI_DIR}"
+ABS_LLVM_DIR="${PWD}/${LLVM_DIR}"
+ABS_LLVM_BUILD_DIR="${PWD}/${LLVM_BUILD_DIR}"
+ABS_COMPILER_RT_DIR="${PWD}/${COMPILER_RT_DIR}"
+ABS_BINUTILS_DIR="${PWD}/${BINUTILS_DIR}"
+
+# ${A:-a} returns $A if it's set, a else.
+LLVM_REPO_URL=${LLVM_URL:-https://llvm.org/svn/llvm-project}
+
+CDS_URL=https://commondatastorage.googleapis.com/chromium-browser-clang
+
+if [[ -z "$GYP_DEFINES" ]]; then
+  GYP_DEFINES=
+fi
+if [[ -z "$GYP_GENERATORS" ]]; then
+  GYP_GENERATORS=
+fi
+if [[ -z "$LLVM_DOWNLOAD_GOLD_PLUGIN" ]]; then
+  LLVM_DOWNLOAD_GOLD_PLUGIN=
+fi
+
+
+# Die if any command dies, error on undefined variable expansions.
+set -eu
+
+
+if [[ -n ${LLVM_FORCE_HEAD_REVISION:-''} ]]; then
+  # Use a real revision number rather than HEAD to make sure that the stamp file
+  # logic works.
+  CLANG_REVISION=$(svn info "$LLVM_REPO_URL" \
+      | grep 'Revision:' | awk '{ printf $2; }')
+  PACKAGE_VERSION="${CLANG_REVISION}-0"
+fi
+
+OS="$(uname -s)"
+
+# Parse command line options.
+if_needed=
+force_local_build=
+run_tests=
+bootstrap=
+with_android=yes
+chrome_tools="plugins;blink_gc_plugin"
+gcc_toolchain=
+with_patches=yes
+
+if [[ "${OS}" = "Darwin" ]]; then
+  with_android=
+fi
+
+while [[ $# > 0 ]]; do
+  case $1 in
+    --bootstrap)
+      bootstrap=yes
+      ;;
+    --if-needed)
+      if_needed=yes
+      ;;
+    --force-local-build)
+      force_local_build=yes
+      ;;
+    --print-revision)
+      if [[ -n ${LLVM_FORCE_HEAD_REVISION:-''} ]]; then
+        svn info "$LLVM_DIR" | grep 'Revision:' | awk '{ printf $2; }'
+      else
+        echo $PACKAGE_VERSION
+      fi
+      exit 0
+      ;;
+    --run-tests)
+      run_tests=yes
+      ;;
+    --without-android)
+      with_android=
+      ;;
+    --without-patches)
+      with_patches=
+      ;;
+    --with-chrome-tools)
+      shift
+      if [[ $# == 0 ]]; then
+        echo "--with-chrome-tools requires an argument."
+        exit 1
+      fi
+      chrome_tools=$1
+      ;;
+    --gcc-toolchain)
+      shift
+      if [[ $# == 0 ]]; then
+        echo "--gcc-toolchain requires an argument."
+        exit 1
+      fi
+      if [[ -x "$1/bin/gcc" ]]; then
+        gcc_toolchain=$1
+      else
+        echo "Invalid --gcc-toolchain: '$1'."
+        echo "'$1/bin/gcc' does not appear to be valid."
+        exit 1
+      fi
+      ;;
+
+    --help)
+      echo "usage: $0 [--force-local-build] [--if-needed] [--run-tests] "
+      echo "--bootstrap: First build clang with CC, then with itself."
+      echo "--force-local-build: Don't try to download prebuilt binaries."
+      echo "--if-needed: Download clang only if the script thinks it is needed."
+      echo "--run-tests: Run tests after building. Only for local builds."
+      echo "--print-revision: Print current clang revision and exit."
+      echo "--without-android: Don't build ASan Android runtime library."
+      echo "--with-chrome-tools: Select which chrome tools to build." \
+           "Defaults to plugins;blink_gc_plugin."
+      echo "    Example: --with-chrome-tools plugins;empty-string"
+      echo "--gcc-toolchain: Set the prefix for which GCC version should"
+      echo "    be used for building. For example, to use gcc in"
+      echo "    /opt/foo/bin/gcc, use '--gcc-toolchain '/opt/foo"
+      echo "--without-patches: Don't apply local patches."
+      echo
+      exit 1
+      ;;
+    *)
+      echo "Unknown argument: '$1'."
+      echo "Use --help for help."
+      exit 1
+      ;;
+  esac
+  shift
+done
+
+if [[ -n ${LLVM_FORCE_HEAD_REVISION:-''} ]]; then
+  force_local_build=yes
+
+  # Skip local patches when using HEAD: they probably don't apply anymore.
+  with_patches=
+
+  if ! [[ "$GYP_DEFINES" =~ .*OS=android.* ]]; then
+    # Only build the Android ASan rt when targetting Android.
+    with_android=
+  fi
+
+  LLVM_BUILD_TOOLS_DIR="${ABS_LLVM_DIR}/../llvm-build-tools"
+
+  if [[ "${OS}" == "Linux" ]] && [[ -z "${gcc_toolchain}" ]]; then
+    if [[ $(gcc -dumpversion) < "4.7.0" ]]; then
+      # We need a newer GCC version.
+      if [[ ! -e "${LLVM_BUILD_TOOLS_DIR}/gcc482" ]]; then
+        echo "Downloading pre-built GCC 4.8.2..."
+        mkdir -p "${LLVM_BUILD_TOOLS_DIR}"
+        curl --fail -L "${CDS_URL}/tools/gcc482.tgz" | \
+          tar zxf - -C "${LLVM_BUILD_TOOLS_DIR}"
+        echo Done
+      fi
+      gcc_toolchain="${LLVM_BUILD_TOOLS_DIR}/gcc482"
+    else
+      # Always set gcc_toolchain; llvm-symbolizer needs the bundled libstdc++.
+      gcc_toolchain="$(dirname $(dirname $(which gcc)))"
+    fi
+  fi
+
+  if [[ "${OS}" == "Linux" || "${OS}" == "Darwin" ]]; then
+    if [[ $(cmake --version | grep -Eo '[0-9.]+') < "3.0" ]]; then
+      # We need a newer CMake version.
+      if [[ ! -e "${LLVM_BUILD_TOOLS_DIR}/cmake310" ]]; then
+        echo "Downloading pre-built CMake 3.10..."
+        mkdir -p "${LLVM_BUILD_TOOLS_DIR}"
+        curl --fail -L "${CDS_URL}/tools/cmake310_${OS}.tgz" | \
+          tar zxf - -C "${LLVM_BUILD_TOOLS_DIR}"
+        echo Done
+      fi
+      export PATH="${LLVM_BUILD_TOOLS_DIR}/cmake310/bin:${PATH}"
+    fi
+  fi
+
+  echo "LLVM_FORCE_HEAD_REVISION was set; using r${CLANG_REVISION}"
+fi
+
+if [[ -n "$if_needed" ]]; then
+  if [[ "${OS}" == "Darwin" ]]; then
+    # clang is always used on Mac.
+    true
+  elif [[ "${OS}" == "Linux" ]]; then
+    # clang is also aways used on Linux.
+    true
+  elif [[ "$GYP_DEFINES" =~ .*(clang|tsan|asan|lsan|msan)=1.* ]]; then
+    # clang requested via $GYP_DEFINES.
+    true
+  elif [[ -d "${LLVM_BUILD_DIR}" ]]; then
+    # clang previously downloaded, keep it up-to-date.
+    # If you don't want this, delete third_party/llvm-build on your machine.
+    true
+  else
+    # clang wasn't needed, not doing anything.
+    exit 0
+  fi
+fi
+
+
+# Check if there's anything to be done, exit early if not.
+if [[ -f "${STAMP_FILE}" ]]; then
+  PREVIOUSLY_BUILT_REVISON=$(cat "${STAMP_FILE}")
+  if [[ -z "$force_local_build" ]] && \
+       [[ "${PREVIOUSLY_BUILT_REVISON}" = \
+          "${PACKAGE_VERSION}" ]]; then
+    echo "Clang already at ${PACKAGE_VERSION}"
+    exit 0
+  fi
+fi
+# To always force a new build if someone interrupts their build half way.
+rm -f "${STAMP_FILE}"
+
+
+if [[ -z "$force_local_build" ]]; then
+  # Check if there's a prebuilt binary and if so just fetch that. That's faster,
+  # and goma relies on having matching binary hashes on client and server too.
+  CDS_FILE="clang-${PACKAGE_VERSION}.tgz"
+  CDS_OUT_DIR=$(mktemp -d -t clang_download.XXXXXX)
+  CDS_OUTPUT="${CDS_OUT_DIR}/${CDS_FILE}"
+  if [ "${OS}" = "Linux" ]; then
+    CDS_FULL_URL="${CDS_URL}/Linux_x64/${CDS_FILE}"
+  elif [ "${OS}" = "Darwin" ]; then
+    CDS_FULL_URL="${CDS_URL}/Mac/${CDS_FILE}"
+  fi
+  echo Trying to download prebuilt clang
+  if which curl > /dev/null; then
+    curl -L --fail "${CDS_FULL_URL}" -o "${CDS_OUTPUT}" || \
+        rm -rf "${CDS_OUT_DIR}"
+  elif which wget > /dev/null; then
+    wget "${CDS_FULL_URL}" -O "${CDS_OUTPUT}" || rm -rf "${CDS_OUT_DIR}"
+  else
+    echo "Neither curl nor wget found. Please install one of these."
+    exit 1
+  fi
+  if [ -f "${CDS_OUTPUT}" ]; then
+    rm -rf "${LLVM_BUILD_DIR}"
+    mkdir -p "${LLVM_BUILD_DIR}"
+    tar -xzf "${CDS_OUTPUT}" -C "${LLVM_BUILD_DIR}"
+    echo clang "${PACKAGE_VERSION}" unpacked
+    echo "${PACKAGE_VERSION}" > "${STAMP_FILE}"
+    rm -rf "${CDS_OUT_DIR}"
+    # Download the gold plugin if requested to by an environment variable.
+    # This is used by the CFI ClusterFuzz bot.
+    if [[ -n "${LLVM_DOWNLOAD_GOLD_PLUGIN}" ]]; then
+      ${THIS_DIR}/../../../build/download_gold_plugin.py
+    fi
+    exit 0
+  else
+    echo Did not find prebuilt clang "${PACKAGE_VERSION}", building
+  fi
+fi
+
+if [[ -n "${with_android}" ]] && ! [[ -d "${ANDROID_NDK_DIR}" ]]; then
+  echo "Android NDK not found at ${ANDROID_NDK_DIR}"
+  echo "The Android NDK is needed to build a Clang whose -fsanitize=address"
+  echo "works on Android. See "
+  echo "http://code.google.com/p/chromium/wiki/AndroidBuildInstructions for how"
+  echo "to install the NDK, or pass --without-android."
+  exit 1
+fi
+
+# Check that cmake and ninja are available.
+if ! which cmake > /dev/null; then
+  echo "CMake needed to build clang; please install"
+  exit 1
+fi
+if ! which ninja > /dev/null; then
+  echo "ninja needed to build clang, please install"
+  exit 1
+fi
+
+echo Reverting previously patched files
+for i in \
+      "${CLANG_DIR}/test/Index/crash-recovery-modules.m" \
+      "${CLANG_DIR}/unittests/libclang/LibclangTest.cpp" \
+      "${COMPILER_RT_DIR}/lib/asan/asan_rtl.cc" \
+      "${COMPILER_RT_DIR}/test/asan/TestCases/Linux/new_array_cookie_test.cc" \
+      "${LLVM_DIR}/test/DebugInfo/gmlt.ll" \
+      "${LLVM_DIR}/lib/CodeGen/SpillPlacement.cpp" \
+      "${LLVM_DIR}/lib/CodeGen/SpillPlacement.h" \
+      "${LLVM_DIR}/lib/Transforms/Instrumentation/MemorySanitizer.cpp" \
+      "${CLANG_DIR}/test/Driver/env.c" \
+      "${CLANG_DIR}/lib/Frontend/InitPreprocessor.cpp" \
+      "${CLANG_DIR}/test/Frontend/exceptions.c" \
+      "${CLANG_DIR}/test/Preprocessor/predefined-exceptions.m" \
+      "${LLVM_DIR}/test/Bindings/Go/go.test" \
+      "${CLANG_DIR}/lib/Parse/ParseExpr.cpp" \
+      "${CLANG_DIR}/lib/Parse/ParseTemplate.cpp" \
+      "${CLANG_DIR}/lib/Sema/SemaDeclCXX.cpp" \
+      "${CLANG_DIR}/lib/Sema/SemaExprCXX.cpp" \
+      "${CLANG_DIR}/test/SemaCXX/default2.cpp" \
+      "${CLANG_DIR}/test/SemaCXX/typo-correction-delayed.cpp" \
+      "${COMPILER_RT_DIR}/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc" \
+      "${COMPILER_RT_DIR}/test/tsan/signal_segv_handler.cc" \
+      "${COMPILER_RT_DIR}/lib/sanitizer_common/sanitizer_coverage_libcdep.cc" \
+      "${COMPILER_RT_DIR}/cmake/config-ix.cmake" \
+      "${COMPILER_RT_DIR}/CMakeLists.txt" \
+      "${COMPILER_RT_DIR}/lib/ubsan/ubsan_platform.h" \
+      ; do
+  if [[ -e "${i}" ]]; then
+    rm -f "${i}"  # For unversioned files.
+    svn revert "${i}"
+  fi;
+done
+
+echo Remove the Clang tools shim dir
+CHROME_TOOLS_SHIM_DIR=${ABS_LLVM_DIR}/tools/chrometools
+rm -rfv ${CHROME_TOOLS_SHIM_DIR}
+
+echo Getting LLVM r"${CLANG_REVISION}" in "${LLVM_DIR}"
+if ! svn co --force "${LLVM_REPO_URL}/llvm/trunk@${CLANG_REVISION}" \
+                    "${LLVM_DIR}"; then
+  echo Checkout failed, retrying
+  rm -rf "${LLVM_DIR}"
+  svn co --force "${LLVM_REPO_URL}/llvm/trunk@${CLANG_REVISION}" "${LLVM_DIR}"
+fi
+
+echo Getting clang r"${CLANG_REVISION}" in "${CLANG_DIR}"
+svn co --force "${LLVM_REPO_URL}/cfe/trunk@${CLANG_REVISION}" "${CLANG_DIR}"
+
+# We have moved from building compiler-rt in the LLVM tree, to a separate
+# directory. Nuke any previous checkout to avoid building it.
+rm -rf "${LLVM_DIR}/projects/compiler-rt"
+
+echo Getting compiler-rt r"${CLANG_REVISION}" in "${COMPILER_RT_DIR}"
+svn co --force "${LLVM_REPO_URL}/compiler-rt/trunk@${CLANG_REVISION}" \
+               "${COMPILER_RT_DIR}"
+
+# clang needs a libc++ checkout, else -stdlib=libc++ won't find includes
+# (i.e. this is needed for bootstrap builds).
+if [ "${OS}" = "Darwin" ]; then
+  echo Getting libc++ r"${CLANG_REVISION}" in "${LIBCXX_DIR}"
+  svn co --force "${LLVM_REPO_URL}/libcxx/trunk@${CLANG_REVISION}" \
+                 "${LIBCXX_DIR}"
+fi
+
+# While we're bundling our own libc++ on OS X, we need to compile libc++abi
+# into it too (since OS X 10.6 doesn't have libc++abi.dylib either).
+if [ "${OS}" = "Darwin" ]; then
+  echo Getting libc++abi r"${CLANG_REVISION}" in "${LIBCXXABI_DIR}"
+  svn co --force "${LLVM_REPO_URL}/libcxxabi/trunk@${CLANG_REVISION}" \
+                 "${LIBCXXABI_DIR}"
+fi
+
+if [[ -n "$with_patches" ]]; then
+
+  # Apply patch for tests failing with --disable-pthreads (llvm.org/PR11974)
+  pushd "${CLANG_DIR}"
+  cat << 'EOF' |
+--- test/Index/crash-recovery-modules.m	(revision 202554)
++++ test/Index/crash-recovery-modules.m	(working copy)
+@@ -12,6 +12,8 @@
+ 
+ // REQUIRES: crash-recovery
+ // REQUIRES: shell
++// XFAIL: *
++//    (PR11974)
+ 
+ @import Crash;
+EOF
+patch -p0
+popd
+
+pushd "${CLANG_DIR}"
+cat << 'EOF' |
+--- unittests/libclang/LibclangTest.cpp (revision 215949)
++++ unittests/libclang/LibclangTest.cpp (working copy)
+@@ -431,7 +431,7 @@
+   EXPECT_EQ(0U, clang_getNumDiagnostics(ClangTU));
+ }
+
+-TEST_F(LibclangReparseTest, ReparseWithModule) {
++TEST_F(LibclangReparseTest, DISABLED_ReparseWithModule) {
+   const char *HeaderTop = "#ifndef H\n#define H\nstruct Foo { int bar;";
+   const char *HeaderBottom = "\n};\n#endif\n";
+   const char *MFile = "#include \"HeaderFile.h\"\nint main() {"
+EOF
+  patch -p0
+  popd
+
+  # This Go bindings test doesn't work after the bootstrap build on Linux. (PR21552)
+  pushd "${LLVM_DIR}"
+  cat << 'EOF' |
+--- test/Bindings/Go/go.test    (revision 223109)
++++ test/Bindings/Go/go.test    (working copy)
+@@ -1,3 +1,3 @@
+-; RUN: llvm-go test llvm.org/llvm/bindings/go/llvm
++; RUN: true
+ 
+ ; REQUIRES: shell
+EOF
+  patch -p0
+  popd
+
+  # The UBSan run-time, which is now bundled with the ASan run-time, doesn't work
+  # on Mac OS X 10.8 (PR23539).
+  pushd "${COMPILER_RT_DIR}"
+  cat << 'EOF' |
+Index: CMakeLists.txt
+===================================================================
+--- CMakeLists.txt	(revision 241602)
++++ CMakeLists.txt	(working copy)
+@@ -305,6 +305,7 @@
+       list(APPEND SANITIZER_COMMON_SUPPORTED_OS iossim)
+     endif()
+   endif()
++  set(SANITIZER_MIN_OSX_VERSION "10.7")
+   if(SANITIZER_MIN_OSX_VERSION VERSION_LESS "10.7")
+     message(FATAL_ERROR "Too old OS X version: ${SANITIZER_MIN_OSX_VERSION}")
+   endif()
+EOF
+  patch -p0
+  popd
+
+fi
+
+# Echo all commands.
+set -x
+
+# Set default values for CC and CXX if they're not set in the environment.
+CC=${CC:-cc}
+CXX=${CXX:-c++}
+
+if [[ -n "${gcc_toolchain}" ]]; then
+  # Use the specified gcc installation for building.
+  CC="$gcc_toolchain/bin/gcc"
+  CXX="$gcc_toolchain/bin/g++"
+  # Set LD_LIBRARY_PATH to make auxiliary targets (tablegen, bootstrap compiler,
+  # etc.) find the .so.
+  export LD_LIBRARY_PATH="$(dirname $(${CXX} -print-file-name=libstdc++.so.6))"
+fi
+
+CFLAGS=""
+CXXFLAGS=""
+LDFLAGS=""
+
+# LLVM uses C++11 starting in llvm 3.5. On Linux, this means libstdc++4.7+ is
+# needed, on OS X it requires libc++. clang only automatically links to libc++
+# when targeting OS X 10.9+, so add stdlib=libc++ explicitly so clang can run on
+# OS X versions as old as 10.7.
+# TODO(thakis): Some bots are still on 10.6 (nacl...), so for now bundle
+# libc++.dylib.  Remove this once all bots are on 10.7+, then use
+# -DLLVM_ENABLE_LIBCXX=ON and change deployment_target to 10.7.
+deployment_target=""
+
+if [ "${OS}" = "Darwin" ]; then
+  # When building on 10.9, /usr/include usually doesn't exist, and while
+  # Xcode's clang automatically sets a sysroot, self-built clangs don't.
+  CFLAGS="-isysroot $(xcrun --show-sdk-path)"
+  CXXFLAGS="-stdlib=libc++ -nostdinc++ -I${ABS_LIBCXX_DIR}/include ${CFLAGS}"
+
+  if [[ -n "${bootstrap}" ]]; then
+    deployment_target=10.6
+  fi
+fi
+
+# Build bootstrap clang if requested.
+if [[ -n "${bootstrap}" ]]; then
+  ABS_INSTALL_DIR="${PWD}/${LLVM_BOOTSTRAP_INSTALL_DIR}"
+  echo "Building bootstrap compiler"
+  mkdir -p "${LLVM_BOOTSTRAP_DIR}"
+  pushd "${LLVM_BOOTSTRAP_DIR}"
+
+  cmake -GNinja \
+      -DCMAKE_BUILD_TYPE=Release \
+      -DLLVM_ENABLE_ASSERTIONS=ON \
+      -DLLVM_TARGETS_TO_BUILD=host \
+      -DLLVM_ENABLE_THREADS=OFF \
+      -DCMAKE_INSTALL_PREFIX="${ABS_INSTALL_DIR}" \
+      -DCMAKE_C_COMPILER="${CC}" \
+      -DCMAKE_CXX_COMPILER="${CXX}" \
+      -DCMAKE_C_FLAGS="${CFLAGS}" \
+      -DCMAKE_CXX_FLAGS="${CXXFLAGS}" \
+      ../llvm
+
+  ninja
+  if [[ -n "${run_tests}" ]]; then
+    ninja check-all
+  fi
+
+  ninja install
+  if [[ -n "${gcc_toolchain}" ]]; then
+    # Copy that gcc's stdlibc++.so.6 to the build dir, so the bootstrap
+    # compiler can start.
+    cp -v "$(${CXX} -print-file-name=libstdc++.so.6)" \
+      "${ABS_INSTALL_DIR}/lib/"
+  fi
+
+  popd
+  CC="${ABS_INSTALL_DIR}/bin/clang"
+  CXX="${ABS_INSTALL_DIR}/bin/clang++"
+
+  if [[ -n "${gcc_toolchain}" ]]; then
+    # Tell the bootstrap compiler to use a specific gcc prefix to search
+    # for standard library headers and shared object file.
+    CFLAGS="--gcc-toolchain=${gcc_toolchain}"
+    CXXFLAGS="--gcc-toolchain=${gcc_toolchain}"
+  fi
+
+  echo "Building final compiler"
+fi
+
+# Build clang (in a separate directory).
+# The clang bots have this path hardcoded in built/scripts/slave/compile.py,
+# so if you change it you also need to change these links.
+mkdir -p "${LLVM_BUILD_DIR}"
+pushd "${LLVM_BUILD_DIR}"
+
+# Build libc++.dylib while some bots are still on OS X 10.6.
+if [ "${OS}" = "Darwin" ]; then
+  rm -rf libcxxbuild
+  LIBCXXFLAGS="-O3 -std=c++11 -fstrict-aliasing"
+
+  # libcxx and libcxxabi both have a file stdexcept.cpp, so put their .o files
+  # into different subdirectories.
+  mkdir -p libcxxbuild/libcxx
+  pushd libcxxbuild/libcxx
+  ${CXX:-c++} -c ${CXXFLAGS} ${LIBCXXFLAGS} "${ABS_LIBCXX_DIR}"/src/*.cpp
+  popd
+
+  mkdir -p libcxxbuild/libcxxabi
+  pushd libcxxbuild/libcxxabi
+  ${CXX:-c++} -c ${CXXFLAGS} ${LIBCXXFLAGS} "${ABS_LIBCXXABI_DIR}"/src/*.cpp -I"${ABS_LIBCXXABI_DIR}/include"
+  popd
+
+  pushd libcxxbuild
+  ${CC:-cc} libcxx/*.o libcxxabi/*.o -o libc++.1.dylib -dynamiclib \
+    -nodefaultlibs -current_version 1 -compatibility_version 1 \
+    -lSystem -install_name @executable_path/libc++.dylib \
+    -Wl,-unexported_symbols_list,${ABS_LIBCXX_DIR}/lib/libc++unexp.exp \
+    -Wl,-force_symbols_not_weak_list,${ABS_LIBCXX_DIR}/lib/notweak.exp \
+    -Wl,-force_symbols_weak_list,${ABS_LIBCXX_DIR}/lib/weak.exp
+  ln -sf libc++.1.dylib libc++.dylib
+  popd
+  LDFLAGS+="-stdlib=libc++ -L${PWD}/libcxxbuild"
+
+  if [[ -n "${bootstrap}" ]]; then
+    # Now that the libc++ headers have been installed and libc++.dylib is built,
+    # delete the libc++ checkout again so that it's not part of the main
+    # build below -- the libc++(abi) tests don't pass on OS X in bootstrap
+    # builds (http://llvm.org/PR24068)
+    rm -rf "${ABS_LIBCXX_DIR}"
+    rm -rf "${ABS_LIBCXXABI_DIR}"
+    CXXFLAGS="-stdlib=libc++ -nostdinc++ -I${ABS_INSTALL_DIR}/include/c++/v1 ${CFLAGS}"
+  fi
+fi
+
+# Find the binutils include dir for the gold plugin.
+BINUTILS_INCDIR=""
+if [ "${OS}" = "Linux" ]; then
+  BINUTILS_INCDIR="${ABS_BINUTILS_DIR}/Linux_x64/Release/include"
+fi
+
+
+# If building at head, define a macro that plugins can use for #ifdefing
+# out code that builds at head, but not at CLANG_REVISION or vice versa.
+if [[ -n ${LLVM_FORCE_HEAD_REVISION:-''} ]]; then
+  CFLAGS="${CFLAGS} -DLLVM_FORCE_HEAD_REVISION"
+  CXXFLAGS="${CXXFLAGS} -DLLVM_FORCE_HEAD_REVISION"
+fi
+
+# Hook the Chromium tools into the LLVM build. Several Chromium tools have
+# dependencies on LLVM/Clang libraries. The LLVM build detects implicit tools
+# in the tools subdirectory, so install a shim CMakeLists.txt that forwards to
+# the real directory for the Chromium tools.
+# Note that the shim directory name intentionally has no _ or _. The implicit
+# tool detection logic munges them in a weird way.
+mkdir -v ${CHROME_TOOLS_SHIM_DIR}
+cat > ${CHROME_TOOLS_SHIM_DIR}/CMakeLists.txt << EOF
+# Since tools/clang isn't actually a subdirectory, use the two argument version
+# to specify where build artifacts go. CMake doesn't allow reusing the same
+# binary dir for multiple source dirs, so the build artifacts have to go into a
+# subdirectory...
+add_subdirectory(\${CHROMIUM_TOOLS_SRC} \${CMAKE_CURRENT_BINARY_DIR}/a)
+EOF
+rm -fv CMakeCache.txt
+MACOSX_DEPLOYMENT_TARGET=${deployment_target} cmake -GNinja \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DLLVM_ENABLE_ASSERTIONS=ON \
+    -DLLVM_ENABLE_THREADS=OFF \
+    -DLLVM_BINUTILS_INCDIR="${BINUTILS_INCDIR}" \
+    -DCMAKE_C_COMPILER="${CC}" \
+    -DCMAKE_CXX_COMPILER="${CXX}" \
+    -DCMAKE_C_FLAGS="${CFLAGS}" \
+    -DCMAKE_CXX_FLAGS="${CXXFLAGS}" \
+    -DCMAKE_EXE_LINKER_FLAGS="${LDFLAGS}" \
+    -DCMAKE_SHARED_LINKER_FLAGS="${LDFLAGS}" \
+    -DCMAKE_MODULE_LINKER_FLAGS="${LDFLAGS}" \
+    -DCMAKE_INSTALL_PREFIX="${ABS_LLVM_BUILD_DIR}" \
+    -DCHROMIUM_TOOLS_SRC="${ABS_CHROMIUM_TOOLS_DIR}" \
+    -DCHROMIUM_TOOLS="${chrome_tools}" \
+    "${ABS_LLVM_DIR}"
+env
+
+if [[ -n "${gcc_toolchain}" ]]; then
+  # Copy in the right stdlibc++.so.6 so clang can start.
+  mkdir -p lib
+  cp -v "$(${CXX} ${CXXFLAGS} -print-file-name=libstdc++.so.6)" lib/
+fi
+
+ninja
+# If any Chromium tools were built, install those now.
+if [[ -n "${chrome_tools}" ]]; then
+  ninja cr-install
+fi
+
+STRIP_FLAGS=
+if [ "${OS}" = "Darwin" ]; then
+  # See http://crbug.com/256342
+  STRIP_FLAGS=-x
+
+  cp libcxxbuild/libc++.1.dylib bin/
+fi
+strip ${STRIP_FLAGS} bin/clang
+popd
+
+# Build compiler-rt out-of-tree.
+mkdir -p "${COMPILER_RT_BUILD_DIR}"
+pushd "${COMPILER_RT_BUILD_DIR}"
+
+rm -fv CMakeCache.txt
+MACOSX_DEPLOYMENT_TARGET=${deployment_target} cmake -GNinja \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DLLVM_ENABLE_ASSERTIONS=ON \
+    -DLLVM_ENABLE_THREADS=OFF \
+    -DCMAKE_C_COMPILER="${CC}" \
+    -DCMAKE_CXX_COMPILER="${CXX}" \
+    -DLLVM_CONFIG_PATH="${ABS_LLVM_BUILD_DIR}/bin/llvm-config" \
+    "${ABS_COMPILER_RT_DIR}"
+
+ninja
+
+# Copy selected output to the main tree.
+# Darwin doesn't support cp --parents, so pipe through tar instead.
+CLANG_VERSION=$("${ABS_LLVM_BUILD_DIR}/bin/clang" --version | \
+     sed -ne 's/clang version \([0-9]\.[0-9]\.[0-9]\).*/\1/p')
+ABS_LLVM_CLANG_LIB_DIR="${ABS_LLVM_BUILD_DIR}/lib/clang/${CLANG_VERSION}"
+tar -c *blacklist.txt | tar -C ${ABS_LLVM_CLANG_LIB_DIR} -xv
+tar -c include/sanitizer | tar -C ${ABS_LLVM_CLANG_LIB_DIR} -xv
+if [[ "${OS}" = "Darwin" ]]; then
+  tar -c lib/darwin | tar -C ${ABS_LLVM_CLANG_LIB_DIR} -xv
+else
+  tar -c lib/linux | tar -C ${ABS_LLVM_CLANG_LIB_DIR} -xv
+fi
+
+popd
+
+if [[ -n "${with_android}" ]]; then
+  # Make a standalone Android toolchain.
+  ${ANDROID_NDK_DIR}/build/tools/make-standalone-toolchain.sh \
+      --platform=android-19 \
+      --install-dir="${LLVM_BUILD_DIR}/android-toolchain" \
+      --system=linux-x86_64 \
+      --stl=stlport \
+      --toolchain=arm-linux-androideabi-4.9
+
+  # Android NDK r9d copies a broken unwind.h into the toolchain, see
+  # http://crbug.com/357890
+  rm -v "${LLVM_BUILD_DIR}"/android-toolchain/include/c++/*/unwind.h
+
+  # Build ASan runtime for Android in a separate build tree.
+  mkdir -p ${LLVM_BUILD_DIR}/android
+  pushd ${LLVM_BUILD_DIR}/android
+  rm -fv CMakeCache.txt
+  MACOSX_DEPLOYMENT_TARGET=${deployment_target} cmake -GNinja \
+      -DCMAKE_BUILD_TYPE=Release \
+      -DLLVM_ENABLE_ASSERTIONS=ON \
+      -DLLVM_ENABLE_THREADS=OFF \
+      -DCMAKE_C_COMPILER=${PWD}/../bin/clang \
+      -DCMAKE_CXX_COMPILER=${PWD}/../bin/clang++ \
+      -DLLVM_CONFIG_PATH=${PWD}/../bin/llvm-config \
+      -DCMAKE_C_FLAGS="--target=arm-linux-androideabi --sysroot=${PWD}/../android-toolchain/sysroot -B${PWD}/../android-toolchain" \
+      -DCMAKE_CXX_FLAGS="--target=arm-linux-androideabi --sysroot=${PWD}/../android-toolchain/sysroot -B${PWD}/../android-toolchain" \
+      -DANDROID=1 \
+      "${ABS_COMPILER_RT_DIR}"
+  ninja libclang_rt.asan-arm-android.so
+
+  # And copy it into the main build tree.
+  cp "$(find -name libclang_rt.asan-arm-android.so)" "${ABS_LLVM_CLANG_LIB_DIR}/lib/linux/"
+  popd
+fi
+
+if [[ -n "$run_tests" || -n "${LLVM_FORCE_HEAD_REVISION:-''}" ]]; then
+  # Run Chrome tool tests.
+  ninja -C "${LLVM_BUILD_DIR}" cr-check-all
+fi
+if [[ -n "$run_tests" ]]; then
+  # Run the LLVM and Clang tests.
+  ninja -C "${LLVM_BUILD_DIR}" check-all
+fi
+
+# After everything is done, log success for this revision.
+echo "${PACKAGE_VERSION}" > "${STAMP_FILE}"
diff --git a/tools/gn.py b/tools/gn.py
new file mode 100755
index 00000000000..32335f09b99
--- /dev/null
+++ b/tools/gn.py
@@ -0,0 +1,159 @@
+#!/usr/bin/env python
+# Copyright 2016 The Dart project authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import argparse
+import subprocess
+import sys
+import os
+import utils
+
+HOST_OS = utils.GuessOS()
+HOST_ARCH = utils.GuessArchitecture()
+HOST_CPUS = utils.GuessCpus()
+SCRIPT_DIR = os.path.dirname(sys.argv[0])
+DART_ROOT = os.path.realpath(os.path.join(SCRIPT_DIR, '..'))
+
+def get_out_dir(args):
+  return utils.GetBuildRoot(HOST_OS, args.mode, args.arch, args.os)
+
+def to_command_line(gn_args):
+  def merge(key, value):
+    if type(value) is bool:
+      return '%s=%s' % (key, 'true' if value else 'false')
+    return '%s="%s"' % (key, value)
+  return [merge(x, y) for x, y in gn_args.iteritems()]
+
+def host_cpu_for_arch(arch):
+  if arch in ['ia32', 'arm', 'armv6', 'armv5te', 'mips',
+              'simarm', 'simarmv6', 'simarmv5te', 'simmips', 'simdbc']:
+    return 'x86'
+  if arch in ['x64', 'arm64', 'simarm64', 'simdbc64']:
+    return 'x64'
+
+def target_cpu_for_arch(arch, os):
+  if arch in ['ia32', 'simarm', 'simarmv6', 'simarmv5te', 'simmips']:
+    return 'x86'
+  if arch in ['simarm64']:
+    return 'x64'
+  if arch == 'mips':
+    return 'mipsel'
+  if arch == 'simdbc':
+    return 'arm' if os == 'android' else 'x86'
+  if arch == 'simdbc64':
+    return 'arm64' if os == 'android' else 'x64'
+  return arch
+
+def to_gn_args(args):
+  gn_args = {}
+
+  if args.os == 'host':
+    gn_args['target_os'] = HOST_OS
+  else:
+    gn_args['target_os'] = args.os
+
+  gn_args['dart_target_arch'] = args.arch
+  gn_args['target_cpu'] = target_cpu_for_arch(args.arch, args.os)
+  gn_args['host_cpu'] = host_cpu_for_arch(args.arch)
+
+  # TODO(zra): This is for the observatory, which currently builds using the
+  # checked-in sdk. If/when the observatory no longer builds with the
+  # checked-in sdk, this can be removed.
+  gn_args['dart_host_pub_exe'] = os.path.join(
+      DART_ROOT, 'tools', 'sdks', HOST_OS, 'dart-sdk', 'bin', 'pub')
+
+  # For Fuchsia support, the default is to not compile in the root
+  # certificates.
+  gn_args['dart_use_fallback_root_certificates'] = True
+
+  gn_args['dart_zlib_path'] = "//runtime/bin/zlib"
+
+  gn_args['is_debug'] = args.mode == 'debug'
+  gn_args['is_release'] = args.mode == 'release'
+  gn_args['is_product'] = args.mode == 'product'
+  gn_args['dart_debug'] = args.mode == 'debug'
+
+  # This setting is only meaningful for Flutter. Standalone builds of the VM
+  # should leave this set to 'develop', which causes the build to defer to
+  # 'is_debug', 'is_release' and 'is_product'.
+  gn_args['dart_runtime_mode'] = 'develop'
+
+  gn_args['is_clang'] = args.clang and args.os not in ['android']
+
+  if args.target_sysroot:
+    gn_args['target_sysroot'] = args.target_sysroot
+
+  if args.toolchain_prefix:
+    gn_args['toolchain_prefix'] = args.toolchain_prefix
+
+  goma_dir = os.environ.get('GOMA_DIR')
+  goma_home_dir = os.path.join(os.getenv('HOME', ''), 'goma')
+  if args.goma and goma_dir:
+    gn_args['use_goma'] = True
+    gn_args['goma_dir'] = goma_dir
+  elif args.goma and os.path.exists(goma_home_dir):
+    gn_args['use_goma'] = True
+    gn_args['goma_dir'] = goma_home_dir
+  else:
+    gn_args['use_goma'] = False
+    gn_args['goma_dir'] = None
+
+  return gn_args
+
+def parse_args(args):
+  args = args[1:]
+  parser = argparse.ArgumentParser(description='A script run` gn gen`.')
+
+  parser.add_argument('--mode', '-m',
+      type=str,
+      choices=['debug', 'release', 'product'],
+      default='debug')
+  parser.add_argument('--os',
+      type=str,
+      choices=['host', 'android'],
+      default='host')
+  parser.add_argument('--arch', '-a',
+      type=str,
+      choices=['ia32', 'x64', 'simarm', 'arm', 'simarmv6', 'armv6',
+               'simarmv5te', 'armv5te', 'simmips', 'mips', 'simarm64', 'arm64',
+               'simdbc', 'simdbc64'],
+      default='x64')
+
+  parser.add_argument('--goma', default=True, action='store_true')
+  parser.add_argument('--no-goma', dest='goma', action='store_false')
+
+  parser.add_argument('--clang', default=True, action='store_true')
+  parser.add_argument('--no-clang', dest='clang', action='store_false')
+
+  parser.add_argument('--target-sysroot', '-s', type=str)
+  parser.add_argument('--toolchain-prefix', '-t', type=str)
+
+  return parser.parse_args(args)
+
+def main(argv):
+  args = parse_args(argv)
+
+  if sys.platform.startswith(('cygwin', 'win')):
+    subdir = 'win'
+  elif sys.platform == 'darwin':
+    subdir = 'mac'
+  elif sys.platform.startswith('linux'):
+     subdir = 'linux64'
+  else:
+    raise Error('Unknown platform: ' + sys.platform)
+
+  command = [
+    '%s/buildtools/%s/gn' % (DART_ROOT, subdir),
+    'gen',
+    '--check'
+  ]
+  gn_args = to_command_line(to_gn_args(args))
+  out_dir = get_out_dir(args)
+  print "gn gen --check in %s" % out_dir
+  command.append(out_dir)
+  command.append('--args=%s' % ' '.join(gn_args))
+  return subprocess.call(command, cwd=DART_ROOT)
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv))