This is part of a larger effort to expose the difference between GrDirectContext,
which runs on the GPU thread and can directly perform operations like uploading
textures, and GrRecordingContext, which can only queue up work to be delivered
to the GrDirectContext later.

Additionally create "_next" permutations for all of the test binaries
on Fuchsia, in order to test both code-paths.

Using the #define follow-up CLs can also create a flutter_runner_next
binary that does not contain any legacy integration code.

BUG: 53847

* Add PlatformView support for Fuchsia

This change allows embedding views provided by fuchsia components into
a flutter app running on Fuchsia. This conforms to Flutters idiomatic
approach to composite PlatformView alongside other rendered layers.

This uses the `view embedder` infrastructure to allow
`PlatformViewLayer`
to hold fuchsia views. This is meant to eventually supplant the legacy
`SceneHost` and `ChildViewLayer` mechanism to embed fuchsia `ChildView`.

To see how this will get used check out:
https://fuchsia-review.googlesource.com/c/experiences/+/398536/6/examples/hello_experiences/lib/fuchsia_view.dart

Includes unittests for platform_view.cc.

Note: This change has no impact on the legacy code to embed fuchsia
views.

* Rename OnCreateViewMethodCall to OnCreateView

Same for OnDestroyViewMethodCall to OnDestroyView
Co-authored-by: NSanjay Chouksey <sanjayc@google.com>

Adds a test that verifies that the view of the local time is the same in
the Dart isolate and the process that is running the test.

Specifically, this test is useful to verify that the code paths for
timezone retrieval do not break while the underlying FIDL protocols are
being refactored.

However, since the check is generally useful, the test is written as a
general flutter test.

Running this on Fuchsia required adding `fuchsia.intl.ProfileProvider`
to the CMX file that is used for all build Fuchsia packages.

Testing is a bit involved on Fuchsia.  You must build the Fuchsia
package `fluter/shell/common:shell_tests` and publish it to the dev
repository for your Fuchsia device.  It seems that a way to do so is to
modify the script `flutter/tools/fuchsia/build_fuchsia_artifacts.py` and
modify its function `GetTargetsToBuild` like so:

```
def GetTargetsToBuild(product=False):
  targets_to_build = [
    'flutter/shell/platform/fuchsia:fuchsia',
    'flutter/shell/common:shell_tests',
  ]
  return targets_to_build
```

Next, the Fuchsia packages need to be compiled and published.

Once done, the following `fx` invocation will run the test, assuming
that you have your Fuchsia setup:

```
fx shell run \
    fuchsia-pkg://fuchsia.com/shell_tests#meta/shell_tests.cmx \
    -- --gtest_filter=ShellTest.LocaltimesMatch
```

Use bilinear instead of nearest filter to draw surface texture

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

Tests:
- TextureLayerTest

Fixes https://github.com/flutter/flutter/issues/53445

Fixes https://github.com/flutter/flutter/issues/53117

Test added:
- ShellTest.CanLoadSkSLsFromAsset

This reverts commit f6b8eda7.

Make the test robust even if the json map reorders its keys.

This PR touches variable names, class names, and file names so it's significantly more risky than its predecessor https://github.com/flutter/engine/pull/17329

Due to file name changes, this PR is expected to change the license files.

We haven't rename `shell/gpu` to `shell/raster` yet. It should be optional but I think it's better to have `raster_surface_software.cc` than `gpu_surface_software.cc`.

Re-enabling tracked in https://github.com/flutter/flutter/issues/53399.

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

Fixes https://github.com/flutter/flutter/issues/53114

This reverts commit fdabcadd.

This was already enabled by-default in AOT mode in [0] - which made the
gen_snapshot invocations use "--lazy-async-stacks --no-causal-async-stacks".

See go/dart-10x-faster-async for more information.

[0] https://github.com/flutter/flutter/commit/347823234fd

This also adds a dependency on SwiftShader's Vulkan frontend.

This paves the way for us to have shell_unittests backed by different rendering APIs (e.g. OpenGL, Vulkan, Metal).

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.

This is a non-breaking addition to the stable Flutter Embedder API and exposes a
subset of the functionality provided by Dart_PostCObject API in a stable and
tested manner to custom embedder implementations.

Send port acquisition can currently be done as described in the unit-test but
there may be opportunities to extend this API in the future to access ports more
easily or create ports from the native side.

The following capabilities of the the Dart_PostCObject API are explicitly NOT
exposed:
* Object arrays: This allows callers to create complex object graphs but only
  using the primitives specified in the native API. I could find no current use
  case for this and would have made the implementation a lot more complex. This
  is something we can add in the future if necessary however.
* Capabilities and ports: Again no use cases and I honestly I didn’t understand
  how to use capabilities. If needed, these can be added at a later point by
  appending to the union.

Fixes https://github.com/flutter/flutter/issues/46624
Fixes b/145982720

This gives us a time closer to when the frame will be rendered on
screen.

Fixes: https://github.com/flutter/flutter/issues/10850

This makes it so that the platform views can be passed
an arbitraty CreateVsyncWaiter callback that lets us inject
a vsync waiter other than just the simulated monotonic vsync waiter
that currently exists.

* 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

The converters are still in a separate target that must be included manually. This allows targets that depend on FML but not Dart runtime not have to depend on the runtime.

Adds a test that includes this target and tests image decompression from assets. There is also a test for the standalone DartConvertor in shell_unittests but not in fml_unittests be cause FML uni-tests cannot yet launch a VM. I will work on adding fixtures for those.

This ensures we rasterize into the canvas passed in as subclasses may reimplement AcquireFrame in different ways that don't utilize the canvas object passed in (such as Fuchsia's flutter_runner::CompositorContext).

This reverts commit f456423c.

This is being reverted because it caused flutter/flutter#45098
(images don't load on iOS).

Investigation is tracked in https://github.com/flutter/flutter/issues/43192