* Manual merge or Dart into flutter a3815b6590...24c7666def

dart-lang/sdk@24c7666def Update tests that have the current version number hardcoded
dart-lang/sdk@f88ce7aef5 Increase Dart version to 2.10

* Update language version.

* Update license.

* Hpdate language version.

* Update license.

Use bilinear instead of nearest filter to draw surface texture

Related Issues:
https://github.com/flutter/flutter/issues/53080

Tests:
- TextureLayerTest

* apply null safety syntax to mobile dart:ui

1. Simple "GPU thread" to "raster thread" replacement.

2. Regex replace "GPU([\n\r\s]+//+ thread)" with "raster$1".

3. Regex replace "// gpu$" with "// raster".

4. Simple test change.

5. Run ci/format.sh

We believe this may be implicated in a Windows-specific crash during the
Flutter Gallery integration test.

See:
https://github.com/flutter/flutter/issues/51896

This reverts commit f9b78c5d.

Image
Codec
FrameInfo
Scene/Picture toImage

* opt out dart:ui from nnbd

* Annotate tests as well

web_ui support coming in https://github.com/flutter/flutter/issues/47163

This reverts commit 6ea69a0d.

On top of the revert, it reverted a commit in the PR:
https://github.com/flutter/engine/pull/14024

This reverts commit ea67e5b0b930ebf552bc7dbd678a35ee6a129c39.

This reverts commit d117ac97.

* Remove erroneous ChildView opacity

* Wire frame metrics through contexts

* Maintain layer stack inside of SceneBuilder

* Remove EnsureSingleChild

* Centralize system-composite and elevation logic

* Wire up OpacityLayer to Scenic

Make ImageFilter objects comparable and printable.

This will help in areas in the Widget and RenderObject trees which try to avoid marking objects for updates if a setter is called with the same value (previously all ImageFilter objects would compare as not equal and appear to be new values).

This reverts commit fcc4ab32.

Fixes https://github.com/flutter/flutter/issues/41394 and other
related correctness issues.

TBR: @arbreng @jason-simmons @mehmetf 

On Fuchsia, add a build flag for compositing OpacityLayers using the system
compositor vs Skia, which exposes a fastpath for opacity via Scenic.
This will only work under certain circumstances, in particular nested
OpacityLayers will not render correctly!

On Fuchsia, add a build flag for compositing PhysicalShapeLayers using
the system compositor vs Skia. Set to off by default, which restores
performant shadows on Fuchsia.

Remove the opacity exposed from ChildView, as that was added mistakenly.

Finally, we centralize the logic for switching between the
system-composited and in-process-composited paths inside of
ContainerLayer. We also centralize the logic for computing elevation
there. This allows the removal of many OS_FUCHSIA-specific code-paths.

Test: Ran workstation on Fuchsia; benchmarked before and after
Bug: 23711
Bug: 24163

* Fix broken tests

Add new optional named oldLayer arguments to all push* methods of the SceneBuilder class.

When not null oldLayer signals to the engine that the intent is to update a layer rendered in a previous frame. The engine may optionally use that signal to reuse the resources allocated for that layer in the previous frame. For example, on the Web we can reuse existing DOM nodes and some of their properties and move fewer nodes around the tree.

The return type of each push method has been tightened up. Instead of having all methods return the same EngineLayer type, each method has its own unique layer type, e.g. OffsetEngineLayer. oldLayer parameters match the returned type. This prevents the framework (and other developers using dart:ui directly) from accidentally supplying an engine layer of the wrong type.

SCN-947 #comment
SCN-1291 #comment

It should return void as SceneBuilder::addRetained is returning void.
Thanks yjbanov@ for finding this typo!

Dart lints added:
* Avoid optional new
* Avoid optional const
* Prefer single quotes
* Prefer default assignment `=`

Fixes flutter/flutter#31650

* Revert "fix toString (#8688)"

This reverts commit 9fa73367.

* Revert "Make Rect and RRect use 64 bit doubles, and make them const-able (#8565)"

This reverts commit c1231527.

* Make Rect and RRect 64bit and const-able

This reverts commit 0b36d3e2.

Fix the spelling errors in the dartdocs for the engine.

There are no functionality changes here, just documentation fixes.

The defaultClipBehavior is no longer used anywhere in the Flutter framework and Google3.

Most changes are trivial except pushTransform. In pushTransform, matrix4 is an Dart object and it has to be released before we can return a new Dart object (EngineLayer).

* Add missing entry-points.

* Fix lint