27653 Move tests (cla: yes, platform-web)

27654 Roll Skia from 8e51bad14f7f to ad858e76e339 (3 revisions) (cla: yes, waiting for tree to go green)

27655 Fix NPE and remove global focus listener when tearing down the view (platform-android, cla: yes, waiting for tree to go green, needs tests)

27656 Roll Skia from ad858e76e339 to d91d2341b9eb (1 revision) (cla: yes, waiting for tree to go green)

27658 Roll Dart SDK from d1c7784d4c7a to 9cc34270bd9b (1 revision) (cla: yes, waiting for tree to go green)

27659 Update test scripts for coverage (cla: yes)