37038 Update SnackBar to the latest Material specs. (cla: yes, f: material design, framework)

37042 Fix selection menu not showing after clear (a: text input, cla: yes, framework)

37043 Tests for Engine ensuring debug-mode apps are attached on iOS. (cla: yes, team, tool)

37044 [flutter_tool] Make a couple file operations synchronous (cla: yes, tool)

37048 use SizedBox instead of Container for building collapsed selection (a: text input, cla: yes, f: cupertino, framework)

37049 Revert Optimize transformRect (cla: yes, framework, waiting for tree to go green)

37055 Revert “Enable selection by default for password text field and expos… (cla: yes, f: cupertino, f: material design, framework)