* Roll engine to 40a37126078f3eee2cd7584da04704908f47cd68
Changes since last roll:
```
40a371260 Remove the content handler for its move to topaz. (#5289)
a262da46f Roll src/third_party/skia/ c06754b04..000e00df1 (12 commits; 1 trivial rolls) (#5288)
f7eab94f4 Roll src/third_party/skia/ bd74e6a02..c06754b04 (1 commit) (#5287)
597fa9ed4 Delegate AppDelegate life-cycle callbacks to plugins via separate object (#5173)
ef0915c10 update docs for Path.getBounds (#5261)
bb1736b7b Roll src/third_party/skia/ 15f1761d9..bd74e6a02 (1 commit; 1 trivial rolls) (#5286)
8c9558b1f Roll src/third_party/skia/ ed4921b9d..15f1761d9 (1 commit) (#5285)
5cbfa9593 Roll src/third_party/skia/ 05da1c16d..ed4921b9d (1 commit) (#5284)
919e8c211 Support for TwoPointConical gradients (#5275)
cdd7e0887 Roll src/third_party/skia/ 94f585ed0..05da1c16d (9 commits; 1 trivial rolls) (#5283)
```
* Include more changes(reverts and a fix)
1. Make CupertinoSwitch use BoxShadow.toPaint() so that it respects
the `debugDisableShadows` flag.
2. Increase blue radius on debug banner
3. Only stroke "synthetic shadow" borders if elevation is positive.
Before this change, if CDPATH was set, and you type (from the flutter root) "bin/flutter --version" you would get an error.
This is because the cd command in follow_links was printing the directory Bash chose from the CDPATH to stdout, causing the path to have a newline in it, which understandably confuses the rest of the script.
In order to avoid checking binaries into flutter/flutter,
this comparator can be used to retrieve golden files from
a sibling flutter/goldens repository.
https://github.com/flutter/flutter/issues/16859
Changes since last roll:
```
ae0d3a553 Roll dart to 2765fcf2aecd3841d082fedaeafc00a73a965f8c. (#5160)
73b835c33 Roll src/third_party/skia/ 0caef298c..20fa1e94a (1 commit) (#5159)
f5c7cb366 Roll dart to b298fc6d8f6a0e1aa841dbbdda26663d6012a79a. (#5155)
93b85ee68 Add Android accessibility bridge support for "longPress" and "tap" semantic events
862d13c6f Roll src/third_party/skia/ 97b48a9c7..0caef298c (6 commits) (#5158)
9b7cc44df Dart bindings own the FDIO namespace. Release the engine side reference to the handle after bindings are setup. (#5156)
8896bd35a Roll src/third_party/skia/ f9ab22385..97b48a9c7 (11 commits; 1 trivial rolls) (#5154)
77910baad Roll src/third_party/skia/ 2050565fe..f9ab22385 (11 commits) (#5151)
0667cba31 Roll src/third_party/skia/ 3fef39d94..2050565fe (2 commits) (#5150)
5da171634 Roll src/third_party/skia/ ef4142a9b..3fef39d94 (1 commit) (#5148)
4ec4b3870 Roll src/third_party/skia/ c86c5c014..ef4142a9b (2 commits) (#5147)
d5c111717 Roll dart to 011676641a8b4b77bb372384c712709cbf037675 (#5146)
beb988c60 Roll src/third_party/skia/ 91368c9b9..c86c5c014 (4 commits) (#5145)
a58eabf14 Roll src/third_party/skia/ dc3192b30..91368c9b9 (12 commits; 1 trivial rolls) (#5144)
```
Changes since the last roll:
```
e11905c6e Add tooltip method to Android AccessibilityBridge (#5103)
2ee36e270 Always enable verbose logging on fuchsia. (#5104)
131349f83 Update flutter runner process name to reflect last running shell. (#5102)
ad9826cbb Roll src/third_party/skia/ c79e2d155..47ed6f10e (10 commits; 1 trivial rolls) (#5100)
7617d2889 libtxt: post-process glyph positions in order to accurately right-justify text (#5093)
895c965ce Set file modified callback. (#5096)
956f3eeca Roll src/third_party/skia/ 5c9369eb1..c79e2d155 (7 commits) (#5099)
6e5112214 Roll src/third_party/skia/ 643ab1bf5..5c9369eb1 (1 commit; 1 trivial rolls) (#5098)
a9180ca20 Roll src/third_party/skia/ 6b043cb9c..643ab1bf5 (3 commits; 3 trivial rolls) (#5097)
82d461049 Roll src/third_party/skia/ 1366282bc..6b043cb9c (2 commits) (#5095)
fb4926e65 Roll src/third_party/skia/ 580aee2fa..1366282bc (2 commits) (#5094)
c249b7026 Path metrics/getBounds/combinations again (#4957)
df255b828 Roll src/third_party/skia/ de5cffbc4..580aee2fa (16 commits) (#5092)
e44e1b49f Initial plugin support for background downloads + content fetching (#5082)
78f8a0f45 [fuchsia] Changes for running Dart 2 on flutter_runner. (#5080)
cbec56a3d Roll src/third_party/skia/ 77e95f706..de5cffbc4 (14 commits) (#5090)
8da9398ed Throw an exception if a secondary isolate tries to send a platform message (#5069)
```
flutter/engine@6a93ef1 Call SkGraphics::Init earlier on Fuchsia.
flutter/engine@f1234eb Add disabled failing test for floating point errors on matrix decomposition.
flutter/engine@ac68263 Hold a global reference to the AssetManager Java object backing the APKAssetProvider
flutter/engine@0e95bb2 Roll src/third_party/skia/ 2d2c1e32c..058f2e6ed (35 commits; 1 trivial rolls)
flutter/engine@3e20562 Roll src/third_party/skia/ 5209d7fce..2d2c1e32c (42 commits; 1 trivial rolls)
flutter/engine@a20fd83 [fuchsia] Remove dead package file generation from core snapshots.
flutter/engine@79b9ffb Fixup Fuchsia content handler post shell refactor.
This engine roll contains the following commits:
* flutter/engine@09d05a389: Prepare and run child isolates on a VM managed (i.e. no UI) task runner.
* flutter/engine@adee35142: Throw an error or return null if FlutterView.getBitmap fails
This contains the following commits:
flutter/engine@3cc8d82 Fix more Linux unittest targets.
flutter/engine@b6ba69b libtxt: add boxes representing empty lines in GetRectsForRange
flutter/engine@388f019 Enable downscale of very large images when uploading on IO thread
flutter/engine@22e1381 Allow runtime unit-test to perform dynamic symbol resolution for Dart snapshots.
flutter/engine@59d1366 Don’t build the host shell on target builds.
flutter/engine@7a6b779 Remove the weak pointer factory from the service isolate's DartIsolate object
flutter/engine@d4729ab Update the embedder GN target to use a source set instead of a complete static library.
flutter/engine@8973c73 Implement Scene::toImage for creating a raster image representation of a scene.
flutter/engine@572c584 Configure kernel paths in the embedder if the asset directory contains the kernel assets
flutter/engine@8ed932c Roll src/third_party/skia/ 1cd6098d5..1ccaa6e05 (20 commits)
flutter/engine@a0804f3 Simplify weak pointer factories and allow vending weak pointers on multiple threads.
* Handle error count reported by frontend.
Extend compilation result from single string to a structure(string filename and integer error count).
* Use ?.
* Include engine roll with dart sdk roll.
* parse(onError) -> tryParse
* Make '?? throw' more readable and avoid issue with analyzer
* Fix test so it mocks compiler output including errors count
Changes since last roll:
```
ed303c628 Roll dart sdk again. Previous roll required 23ae4fa098 revert. (#4966)
8cd272733 Revert "Roll dart to 7764e6962e22afcf4b58c4e3cef3147330f3c884. (#4960)" (#4965)
9199b40f2 Revert "Support multiple shells in a single process. (#4932)" (#4964)
6baff4c82 Support multiple shells in a single process. (#4932)
31c5bb427 Roll dart to 7764e6962e22afcf4b58c4e3cef3147330f3c884. (#4960)
c8e4c6984 Avoid copying the contents of large platform message responses (#4947)
5ff527295 Update to use new vulkan GrBackendRenderTarget ctor. (#4962)
0c8993a1a Update to use new vulkan GrBackendRenderTarget ctor (part 2) (#4963)
132ebdda8 Revert "Roll src/third_party/skia/ 9874bf1bc..52e16d984 (135 commits) (#4958)" (#4961)
11882ab9e Roll src/third_party/skia/ 9874bf1bc..52e16d984 (135 commits) (#4958)
```
Add consts
