27371 Set ANDROID_HOME in run_gradle.py (cla: yes, waiting for tree to go green)

27373 Enable Dart compressed pointers for 64-bit mobile targets (cla: yes)

27374 Roll Dart SDK from 3c094fbf2093 to ab009483f343 (2 revisions) (cla: yes, waiting for tree to go green)

27375 [web] fix a few analysis lints (cla: yes, platform-web)

27377 [fuchsia] fix race in DefaultSessionConnection (cla: yes, platform-fuchsia, needs tests)

27382 Revert “Make FlutterFragment usable without requiring it to be attached to an Android Activity.” (platform-android, cla: yes)