22271 Roll Fuchsia Mac SDK from 6yEx5GNGG… to o45EAhxJZ… (cla: yes, waiting for tree to go green)

22272 Remove GetExternalViewEmbedder from surface (cla: yes, platform-android, platform-ios, waiting for tree to go green)

22273 [web] Fix repaint logic for cullrect,transform changes (cla: yes)

22275 Do not involve external_view_embedder in submit frame process if threads are not merged. (cla: yes, platform-ios, waiting for tree to go green)

22276 Roll Fuchsia Linux SDK from oLF1FW-gC… to Esyuo1am1… (cla: yes, waiting for tree to go green)