* Revert "Roll Dart SDK from 9f907e198970 to 37ccceacad41 (3 revisions) (#22069)"

This reverts commit 4f4599b2.

* Revert "Roll Dart SDK from a3d902d8598e to 9f907e198970 (2 revisions) (#22058)"

This reverts commit e51c710e.

* support uri intent launcher in android

* fix comment

Initialize the AssetManager from the application context so that assets from dynamic feature modules can be loaded.

Related to https://github.com/flutter/flutter/issues/65270

This re-lands #20496 and #21780 after fixing the semantics-enabling code that was causing the post-submit web_smoke_test to fail.

Below is the description from the original PR:

This is a PR for converting the dart:ui code in the engine to use a multi-window API. The goal here is to convert from the window singleton to an API that has the concept of multiple windows. Also, I'm matching up the new PlatformDispatcher class to talk directly to the PlatformConfiguration class in the engine. I'm not attempting to actually enable creating multiple windows here, just migrate to an API that has a concept of multiple windows. The multi-window API in this PR currently only ever creates one window.

The design doc for this change is here.

The major changes in this PR:

Move the platfom-specific attributes out of Window, and into the new PlatformDispatcher class that holds all of the platform state, so that the platform code need only update the configuration on this class.
Create FlutterView, FlutterWindow, and SingletonFlutterWindow classes to separate out the concepts of a view (of which there may be multiple in a window), a window (of which there may be multiple on a screen, and they host views), and a window where there is only ever expected to be one (this hosts the entire API of the former Window class, and will eventually be the type of the window singleton).
Next step after this PR lands:

Remove the Window class entirely (it is replaced by SingletonFlutterWindow). Some minor changes in the Framework are needed to switch to using SingletonFlutterWindow directly first.

The Window class still exists in this PR, but will be removed as soon as the framework is converted to point to the SingletonFlutterWindow class instead. They share the same API, just have different names (Window is currently a subclass of SingletonFlutterWindow). The intention is that the Window name will be freed up to use as a widget class name in the framework for managing windows. The singleton called window will remain, and keep the same API it has now.

This reverts commit d2ea378b.

https://skia.googlesource.com/skia.git/+log/5c7bb326a7b3..65674e4c2e56

2020-10-22 kjlubick@google.com [canvaskit] Compile in most gms for testing
2020-10-22 johnstiles@google.com Reland "Add pooling support on iOS."
2020-10-22 egdaniel@google.com Fix asserts for npot tiling in gl.

If this roll has caused a breakage, revert this CL and stop the roller
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* Reland fuchsia external view embedder will be shared with platform view

This reverts commit 9b752790.

* wait for the external view embedder to be initialized before creating
shell

https://dart.googlesource.com/sdk.git/+log/a3d902d8598e..9f907e198970

2020-10-22 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.11.0-244.0.dev
2020-10-21 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.11.0-243.0.dev

If this roll has caused a breakage, revert this CL and stop the roller
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If this roll has caused a breakage, revert this CL and stop the roller
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https://skia.googlesource.com/skia.git/+log/2d2f82c00aeb..5c7bb326a7b3

2020-10-22 johnstiles@google.com Reland "Create a basic IRNode pooling system."
2020-10-22 egdaniel@google.com Revert "Reland "Create a basic IRNode pooling system.""
2020-10-22 egdaniel@google.com Revert "Add pooling support on iOS."
2020-10-22 brianosman@google.com Add much better SkTHashMap visualization to Skia.natvis
2020-10-22 kjlubick@google.com [fuzz] Copy crashing outputs before failing
2020-10-22 johnstiles@google.com Add pooling support on iOS.
2020-10-22 jvanverth@google.com Fix storage class issues for push constant variables.
2020-10-22 skia-autoroll@skia-public.iam.gserviceaccount.com Roll SwiftShader from 84f5eeb6dd9b to e02d8938821a (3 revisions)
2020-10-22 skia-autoroll@skia-public.iam.gserviceaccount.com Roll Chromium from 4bdce889ea35 to 502ec4ce30b3 (465 revisions)
2020-10-22 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ANGLE from e2147a58a233 to d74754378f09 (16 revisions)
2020-10-22 skia-autoroll@skia-public.iam.gserviceaccount.com Roll Dawn from cca03ca6bfe9 to 22505a5afe1f (9 revisions)
2020-10-22 johnstiles@google.com Reland "Create a basic IRNode pooling system."
2020-10-21 fmalita@chromium.org [svg] Add support for preserveAspectRatio
2020-10-21 johnstiles@google.com Pop the symbol table if compilation fails.
2020-10-21 kjlubick@google.com [canvaskit] Load resources into wasm gms/unit tests.
2020-10-21 egdaniel@google.com In Vk don't set dynamic blend constant on Pipeline if we don't use it.
2020-10-21 tdenniston@google.com [svg] Add gradientUnits attribute, value, and parsing
2020-10-21 jlavrova@google.com Underline decorations with gaps and no text
2020-10-21 bsalomon@google.com Reland "Perform bounding rect-relative calcs in full float in GrRRectBlurEffect"
2020-10-21 brianosman@google.com Add several more visualizations to Skia.natvis
2020-10-21 michaelludwig@google.com Make small epsilons more rigorous for gpu gaussian blurs
2020-10-21 johnstiles@google.com Revert "Create a basic IRNode pooling system."
2020-10-21 bsalomon@google.com Revert "Perform bounding rect-relative calcs in full float in GrRRectBlurEffect"
2020-10-21 johnstiles@google.com Migrate additional FPs to `return` instead of `sk_OutColor`.
2020-10-21 johnstiles@google.com Wrap built-in symbol tables when a switch statement is cloned.
2020-10-21 bsalomon@google.com Perform bounding rect-relative calcs in full float in GrRRectBlurEffect
2020-10-21 johnstiles@google.com Create a basic IRNode pooling system.
2020-10-21 robertphillips@google.com Increase encapsulation of GrThreadSafeCache::Entry
2020-10-21 kjlubick@google.com [canvaskit] Fix gm test runner on non-tryjobs
2020-10-21 skia-autoroll@skia-public.iam.gserviceaccount.com Roll SwiftShader from df17a76102df to 84f5eeb6dd9b (3 revisions)
2020-10-21 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ANGLE from 2be35682cd67 to e2147a58a233 (40 revisions)
2020-10-21 skia-autoroll@skia-public.iam.gserviceaccount.com Roll Chromium from 60b90a0bfd24 to 4bdce889ea35 (441 revisions)
2020-10-21 skia-autoroll@skia-public.iam.gserviceaccount.com Roll Dawn from c4593127cbdd to cca03ca6bfe9 (7 revisions)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
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To report a problem with the AutoRoller itself, please file a bug:
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This regression was introduced in https://github.com/flutter/engine/pull/21820
for sound-null safety. The settings used to launch the VM were incorrectly used
to determine the isolate lifecycle callbacks. Since the first shell/engine in
the process also starts the VM, these objects are usually identical. However,
for subsequent engine shell/engine launches, the callbacks attached to the new
settings object would be ignored. The unit-test harness is also structured in
such a way that each test case tears down the VM before the next. So all
existing tests created a bespoke VM for the test run, and, the tests that did
create multiple isolates did not also test attaching callbacks to the settings
object.

Fixes https://github.com/flutter/engine/pull/22041

Embedders that have access to the Dart native API (only Fuchsia now) may perform
library setup in the isolate create callback. The engine used to depend on the
fact the root isolate entrypoint is invoked in the next iteration of message
loop (via the `_startIsolate` trampoline in `isolate_patch.dart`) to ensure that
library setup occur before the main entrypoint was invoked. However, due to
differences in the way in which message loops are setup in Fuchsia, this
entrypoint was run before the callback could be executed. Dart code on Fuchsia
also has the ability to access the underlying event loops directly. This patch
moves the invocation of the create callback to before user dart code has a
chance to run. This difference in behavior on Fuchsia became an issue when the
isolate initialization was reworked in https://github.com/flutter/engine/pull/21820
for null-safety.

Another issue was discovered in that the callback was being invoked twice, I
fixed that too and added a test.

Fixes https://github.com/flutter/flutter/issues/68732

https://dart.googlesource.com/sdk.git/+log/874709e52a99..a3d902d8598e

2020-10-21 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.11.0-242.0.dev

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
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Please CC dart-vm-team@google.com on the revert to ensure that a human
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To report a problem with the AutoRoller itself, please file a bug:
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https://skia.googlesource.com/skia.git/+log/1c823674d957..2d2f82c00aeb

2020-10-20 brianosman@google.com Always declare sk_FragColor in GLSL, even if unused
2020-10-20 ethannicholas@google.com added SkSLNodeArrayWrapper
2020-10-20 reed@google.com update dox for drawPaint
2020-10-20 johnstiles@google.com Wrap built-in symbol tables during inlining.
2020-10-20 johnstiles@google.com Wrap built-in symbol tables when an IRNode is cloned.
2020-10-20 johnstiles@google.com Fix typo in class name.
2020-10-20 robertphillips@google.com Make GrFillRectOp::onPrePrepareDraws also call base class' version
2020-10-20 adlai@google.com Reland "Remove GrContext"
2020-10-20 robertphillips@google.com Rename some of GrThreadSafeCache's member variables
2020-10-20 abarth@google.com [fuchsia] Migrate to new zx::vmar::map method
2020-10-20 mtklein@google.com upstream cl/337571894 with tweaks
2020-10-20 robertphillips@google.com Pull the triangulating path renderer's shape-space triangulation into a helper method
2020-10-20 fmalita@chromium.org [svg] Parse text attributes

If this roll has caused a breakage, revert this CL and stop the roller
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This breaks linting on other targets that include skia headers that do
ifdef checks on SK_VULKAN.

This reverts commit 25d8fa5a.

The new map() method receives its arguments in the same order as the
underlying C system call. This patch should not change any behavior.

https://dart.googlesource.com/sdk.git/+log/fc82eeed7df3..8be6a08153cc

2020-10-20 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.11.0-238.0.dev

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Revert "Reland: Use dispatchKeyEventPreIme, and handle keys sent to InputConnection.sendKeyEvent on Android (#21979)" (#22004)

This reverts commit 3cd70f2c because it causes some failures in web tests.