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
* Fixed ChildSceneLayer elevation issue on Fuchsia.
ChildSceneLayers would draw on top of stacked Flutter content on
Fuchsia if not wrapped up in a Material widget, i.e. a
PhysicalShapeLayer. This patch pushes the logic from there to all
types of Layers.
* Revert "Add flow test fixtures and tests (#13986)"
This reverts commit 620f5281b819f304e8e9e945222e26b17b087cc3.
* Revert "Dynamically determine whether to use offscreen surface based on need (#13976)"
This reverts commit a86ef946563b020108320bbfb974bf7343284fd3.
For https://github.com/flutter/flutter/issues/33807
We still need to make layers' children immutable for full immutability.
That will require us to change the SceneBuilder API to build the layer
bottom up instead of top down (post-order traversal instead of pre-order
traversal).
The overlay surfaces are going to be the same IOSSurface implementation
with the platform views controller set to null (so these are surfaces
that don't support embedding platform views to them).
* Adds a FlutterOverlayView which is a UIView that's showing an
overlay surface.
* Creates an overlay surface for each embedded UIView (done in
FlutterPlatformViewsController).
* Changes CompositeEmbeddedView to return a new canvas.
* Makes the PlatformViewLayer replace the PaintContext's canvas with
the canvas for the overlay view.
* Changed canvas in PaintContext to be a pointer so it can be changed.
TBD in following PRs:
* Copy the current canvas state when replacing a canvas in PaintContext.
* Make FlutterOverlayView work with a GL backend (currently it only
works with software rendering)
