28087 [canvaskit] Optimize CanvasKit platform views in special cases (cla: yes, platform-web)

28089 Roll Dart SDK from 3e8633bcbf8f to bedc39b7a80b (1 revision) (cla: yes, waiting for tree to go green)

28090 Roll Skia from 1049d8206120 to abe39f5cb932 (6 revisions) (cla: yes, waiting for tree to go green)

28091 Revert “Enable Dart compressed pointers for 64-bit mobile targets” (cla: yes, waiting for tree to go green)

28092 Revert “Sets focus before sending a11y focus event in Android” (platform-android, cla: yes)