testOneOverlayAndTwoIntersectingOverlays is failing with impeller turned on.

The test shows "a simple platform view with one overlay and two overlays that intersect with each other and the platform view."

https://github.com/flutter/engine/blob/a59351f31aa18a7eafebfbbffcad46c0154287f5/testing/scenario_app/lib/src/platform_view.dart#L237

$ ./flutter/tools/gn --no-goma --unoptimized --ios --simulator && ninja -C out/ios_debug_sim_unopt scenario_app
$ open out/ios_debug_sim_unopt/scenario_app/Scenarios/Scenarios.xcodeproj

Add FLTEnableImpeller => YES to ios_debug_sim_unopt/scenario_app/Scenarios/Scenarios/Info.plist.

Run -[UnobstructedPlatformViewTests testOneOverlayAndTwoIntersectingOverlays]
Should look like this:

but with impeller on is missing the circle overlays:

See flutter/engine#17049