* Roll Skia to 579f094f1259931c30dfd1623e8e22d74b4a7531

Fixes https://github.com/flutter/flutter/issues/13742

This matches Blink's behavior

Since we've got a vector class, and it has a getter for the magnitude,
why not also a getter for the angle.

* Rolled dart-sdk to bd6cbd1ec7e79730ea1fd8ba01139f4e18a02290

* Updated third_party licenses.

To align with `SemanticsAction`.

This reverts commit d8740c70.

We have a use for this for the internal messaging plugin. Instead of rolling our own, it made sense to add it here especially since it has the mirror functionality (wrap).

Fixes https://github.com/flutter/flutter/issues/13896

* Roll Dart to version 8d7219a5b6a7c2505ff57f23e7cf80da4c724512

* Update third_party license file.

SkTypes.h no longer includes SkMalloc.h

* Fix windows build by using lambda capture workaround

* clang format, add todo

* clang-format again

* This adds rpc call to simply set asset path.

This is needed when doing hot reload to pick up updated assets.

* Move asset_directory fetch for after view_id. Clean up return. Fix formatting.

* Add SetAssetBundlePath methods implementations for mac and ios

* Fix mac mm

* Fix formatting

* Merge and use nullptr

It is moving to the Fuchsia codebase.

* Apply transform to textures on android 

Add support for --strong option in the engine, create a strong mode version of the platform file (#4504)

* Add a --strong option to the front end server so we can use strong mode with preview-dart-2.

* Plumb the --strong option through the dart controller into the VM.

* - Build a strong version of platform.dill for use with the engine.
- Fix a strong mode static error in the assert statement

* Enable asserts when running debug version even in strong mode.

* Use the correct platform dill file for linking when doing the aot builds.

* Fix formatting issue.

This reverts commit 368380cf.

This breaks Flutter external_ui test.

* Revert "Revert "Fix filename handling for Windows. (#4482)" (#4484)"

This reverts commit 929e5b39.

Reverting now since issue with
gen_snapshot(as described in https://github.com/flutter/flutter/issues/13708) was fixed.

* resolve->resolveUri, drop underscores

* Fix underscore

* Apply transform to textures on android

* Remove mention of adb from instructions

This isn't a step we have our users do, so best that we don't do it either.

* Update CONTRIBUTING.md

This reverts commit eee4a1ed.

Original commit caused external_ui integration test failure on Android.

* Roll dart

* Update license