* enable ios safari screenshot tests

* this is the value used for screenshots in the repo.

* change revision

* fix the error made in the gaps

* do not try to fetch on LUCI

* lunix luci migth break existing prs. only skip fetching for mac

* add a placeholder tests for shadow golden test

* try to use iPhone 11 Pro on LUCI

* change the scale and the smoke test image

* add unmerged goldens PR to tests all the screenshots. will be removed later

* change the goldens lock back to flutter/goldens

* change wrong comment on screenshot tests block

* address reviewer comments

* change the commit number for goldens file

* skip canvas blend mode tests

* debugging LUCI error

* debugging LUCI error printing directory contents

* skip one test, remove the debug logs

* change the revision number to include the correct chrome files

Revert "Revert "Adds fuchsia node roles to accessibility bridge updates. (#20385)" (#20936)" (#21367)

This reverts commit 96efe392.

Embedders can now notify shell during startup about the various displays and their corresponding settings.
Adds a notion of Display update type which can later include chages to displays during runtime such as addition / removal / reconfiguration of displays.

We also remove the responsibility of providing the refresh rate from `vsync_waiter` to `DisplayManager`.
Rewires existing platform implementations of the said API to use `Shell::OnDisplayUpdate` to notify the display manager of the startup configuration.

DisplayManager is also thread-safe to account for rasterizer and UI thread accesses.

* Avoid sending a 0 DPR to framework

* check width and height as well

This reverts commit cdc631c4.

When the EncodableValue implementation changed, the old version was
temporarily kept behind an #ifdef to allow temporarily using the old
version, so that the roll would not be blocked. All known existing
clients have migrated, so the legacy version is no longer necessary.

* [gn] Adds a flag to turn off git hash versioning

Without this flag, it is excessively tedious to build Dart SDK
for local testing on Fuchsia, since Fuchsia runner will reject
a Dart SDK without a matching version.

* [gn] Add flag --no-dart-version-git-info

This flag suppresses the SDK stamping by git hash, which allows
deploying self-built Dart SDK.  Without this flag, it is impossible
to build and deploy a development Dart SDK on Fuchsia.

GLFW Error callback useful to clarify reasons of 'glfwInit()' failure.

On some platforms/desktop environments may be really strange failure reasons, like (in my case): "Linux: Failed to initialize inotify: Too many open files", so descriptive error messages helps to solve problem.

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/fuchsia-mac-sdk-flutter-engine
Please CC zra@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/master/autoroll/README.md

* isCloneOf for Image

* Update docs, add missing impl

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/fuchsia-linux-sdk-flutter-engine
Please CC zra@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/master/autoroll/README.md

Fixes https://github.com/flutter/flutter/issues/65619