13160 Revert “Issue 13238: on iOS, force an orientation change when the current orientation is not allowed” (cla: yes)

13161 Enable/tweak web sdk source maps, take 2 (cla: yes)

13162 Document //flutter/runtime/dart_isolate.h (cla: yes)

13163 Manual roll of src/third_party/dart 4131d3d7c4…41b65b27c2 (28 commits) (cla: yes)

13170 Issue 13238: on iOS, force an orientation change when the current orientation is not allowed (cla: yes)

13175 Remove redundant call to updateEditingState in sendKeyEvent (cla: yes)

13176 Add repeatCount to FlutterKeyEvent (cla: yes)