Reduce number of surfaces required when presenting platform views (flutter/engine#43301)
Fixes https://github.com/flutter/flutter/issues/129710
Fixes https://github.com/flutter/flutter/issues/138936
Implements https://flutter.dev/go/optimized-platform-view-layers
## Example
This scene would normally require 5 surfaces, but with the PR it comes
down to 2 (when drawing over platform views) and 1 when all drawing is
outside of platform views).
https://github.com/flutter/flutter/assets/96958/091da832-bfbc-44a2-8da5-d55d84024c96
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