This caused over-aggressive GCs, which vastly increased CPU usage benchmarks.

* Revert "fix build (#20644)"

This reverts commit b59793ee.

* Revert "Hint freed (#19842)"

This reverts commit 3930ac1b.

This reverts commit d16ba48e.

The `ForwardingGestureRecognizers` to have back reference to the `PlatformViewsController` so it can access `FlutterViewController` when its available  (#20708)

The data race: gl_surface_fbo_frame_infos_ in the test context to was appended
to on the raster task runner but read on the platform task runner. This is now
sidestepped by using a callback and pushing that responsibility to the test.
Setting the callback is guarded behind a mutex.

The race condition: The assertions were previously run when the UI thread was
done generating the frames. However, the assertions were run on the results
collected on the raster thread in response the frame requests from UI thread.
Just run the assertions on the raster thread directly.

Fixes https://github.com/flutter/flutter/issues/64344

* Add native stacktrace on iOS

* Add native stacktrace on Android

* format and changing naming to errorWithCode on iOS

* reformat

* Remove stacktrace from decodeEnvelope, not needed.

* Separate encodeErrorEnvelopeWithStacktrace with original encode function

* Add unit tests

* re-format

* change comments for stacktrace

* Remove changes for iOS
Co-authored-by: NBen Li <libe@google.com>

Reland "account for inline placeholders in longest line calculation (#20370)" reverted in (#20669) (#20678)

https://github.com/flutter/flutter/issues/64343