Enable the triple shift experiment

Update the golden for a front_end test which adds additional constant evaluation
information now that the experiment is enabled.

A co19 test will start failing. https://github.com/dart-lang/co19/issues/1062

Change-Id: I18ec586f57deda83f6cd75e476137ab75d50a92f
TEST=No new tests.
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/193747
Auto-Submit: Nate Bosch <nbosch@google.com>
Commit-Queue: Nate Bosch <nbosch@google.com>
Reviewed-by: Leaf Petersen <leafp@google.com>

CHANGELOG.md

@@ -30,6 +30,12 @@ Updated the Linter to `1.3.0`, which includes:
 - new lint: `require_trailing_commas`.
 - new lint: `prefer_null_aware_method_calls`.
 
+### Language
+
+*   Add an unsigned shift right operator `>>>`. Pad with zeroes, ignoring the
+    sign bit. On the web platform `int.>>>` shifts the low 32 bits interpreted
+    as an unsigned integer, so `a >>> b` gives the same result as
+    `a.toUnsigned(32) >>> b` on the VM.
 
 ## 2.13.0
 

pkg/analyzer/lib/src/dart/analysis/experiments.g.dart

@@ -182,7 +182,7 @@ class ExperimentalFeatures {
     isExpired: IsExpired.triple_shift,
     documentation: 'Triple-shift operator',
     experimentalReleaseVersion: null,
-    releaseVersion: null,
+    releaseVersion: Version.parse('2.14.0'),
   );
 
   static final value_class = ExperimentalFeature(
@@ -240,7 +240,7 @@ class IsEnabledByDefault {
   static const bool spread_collections = true;
 
   /// Default state of the experiment "triple-shift"
-  static const bool triple_shift = false;
+  static const bool triple_shift = true;
 
   /// Default state of the experiment "value-class"
   static const bool value_class = false;

pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart

@@ -90,7 +90,7 @@ const Map<ExperimentalFlag, bool> defaultExperimentalFlags = {
   ExperimentalFlag.nonfunctionTypeAliases: true,
   ExperimentalFlag.setLiterals: true,
   ExperimentalFlag.spreadCollections: true,
-  ExperimentalFlag.tripleShift: false,
+  ExperimentalFlag.tripleShift: true,
   ExperimentalFlag.valueClass: false,
   ExperimentalFlag.variance: false,
 };

pkg/front_end/testcases/general/constants/no_experiments/various.dart.weak.expect

@@ -1,19 +1,11 @@
 library;
-//
-// Problems in library:
-//
-// pkg/front_end/testcases/general/constants/no_experiments/various.dart:5:40: Error: Constant evaluation error:
-// const Symbol tripleShiftSymbol = const Symbol(">>>");
-//                                        ^
-// pkg/front_end/testcases/general/constants/no_experiments/various.dart:5:47: Context: The symbol name must be a valid public Dart member name, public constructor name, or library name, optionally qualified, but was '">>>"'.
-// const Symbol tripleShiftSymbol = const Symbol(">>>");
-//                                               ^
-// pkg/front_end/testcases/general/constants/no_experiments/various.dart:5:14: Context: While analyzing:
-// const Symbol tripleShiftSymbol = const Symbol(">>>");
-//              ^
-//
 import self as self;
 import "dart:core" as core;
+import "dart:_internal" as _in;
 
-static const field core::Symbol* tripleShiftSymbol = invalid-expression "The symbol name must be a valid public Dart member name, public constructor name, or library name, optionally qualified, but was '\">>>\"'.";
+static const field core::Symbol* tripleShiftSymbol = #C1;
 static method main() → dynamic {}
+
+constants  {
+  #C1 = #>>>
+}

pkg/front_end/testcases/general/constants/no_experiments/various.dart.weak.outline.expect

@@ -6,3 +6,8 @@ import "dart:_internal" as _in;
 static const field core::Symbol* tripleShiftSymbol = const _in::Symbol::•(">>>");
 static method main() → dynamic
   ;
+
+
+Extra constant evaluation status:
+Evaluated: ConstructorInvocation @ org-dartlang-testcase:///various.dart:5:40 -> SymbolConstant(#>>>)
+Extra constant evaluation: evaluated: 1, effectively constant: 1

pkg/front_end/testcases/general/constants/no_experiments/various.dart.weak.transformed.expect

@@ -1,19 +1,11 @@
 library;
-//
-// Problems in library:
-//
-// pkg/front_end/testcases/general/constants/no_experiments/various.dart:5:40: Error: Constant evaluation error:
-// const Symbol tripleShiftSymbol = const Symbol(">>>");
-//                                        ^
-// pkg/front_end/testcases/general/constants/no_experiments/various.dart:5:47: Context: The symbol name must be a valid public Dart member name, public constructor name, or library name, optionally qualified, but was '">>>"'.
-// const Symbol tripleShiftSymbol = const Symbol(">>>");
-//                                               ^
-// pkg/front_end/testcases/general/constants/no_experiments/various.dart:5:14: Context: While analyzing:
-// const Symbol tripleShiftSymbol = const Symbol(">>>");
-//              ^
-//
 import self as self;
 import "dart:core" as core;
+import "dart:_internal" as _in;
 
-static const field core::Symbol* tripleShiftSymbol = invalid-expression "The symbol name must be a valid public Dart member name, public constructor name, or library name, optionally qualified, but was '\">>>\"'.";
+static const field core::Symbol* tripleShiftSymbol = #C1;
 static method main() → dynamic {}
+
+constants  {
+  #C1 = #>>>
+}

runtime/vm/experimental_features.cc

@@ -18,7 +18,7 @@ namespace dart {
 
 bool GetExperimentalFeatureDefault(ExperimentalFeature feature) {
   constexpr bool kFeatureValues[] = {
-      true, true, true, true, true, true, true,
+      true, true, true, true, true, true, true, true,
   };
   ASSERT(static_cast<size_t>(feature) < ARRAY_SIZE(kFeatureValues));
   return kFeatureValues[static_cast<int>(feature)];
@@ -29,7 +29,7 @@ const char* GetExperimentalFeatureName(ExperimentalFeature feature) {
       "nonfunction-type-aliases", "non-nullable",
       "extension-methods",        "constant-update-2018",
       "control-flow-collections", "set-literals",
-      "spread-collections",
+      "spread-collections",       "triple-shift",
   };
   ASSERT(static_cast<size_t>(feature) < ARRAY_SIZE(kFeatureNames));
   return kFeatureNames[static_cast<int>(feature)];

runtime/vm/experimental_features.h

@@ -21,6 +21,7 @@ enum class ExperimentalFeature {
   control_flow_collections,
   set_literals,
   spread_collections,
+  triple_shift,
 };
 
 bool GetExperimentalFeatureDefault(ExperimentalFeature feature);

tools/experimental_features.yaml

@@ -106,16 +106,6 @@
 current-version: '2.14.0'
 
 features:
-  triple-shift:
-    help: "Triple-shift operator"
-    validation: |
-      class A {
-        operator>>>(int k) => 42;
-      }
-      void main() {
-        if ((A() >>> 1) == 42) print('feature enabled');
-      }
-
   variance:
     help: "Sound variance"
 
@@ -183,3 +173,14 @@ features:
     help: "Spread Collections"
     enabledIn: '2.0.0'
     expired: true
+
+  triple-shift:
+    help: "Triple-shift operator"
+    enabledIn: '2.14.0'
+    validation: |
+      class A {
+        operator>>>(int k) => 42;
+      }
+      void main() {
+        if ((A() >>> 1) == 42) print('feature enabled');
+      }