11798 Manage resource and onscreen contexts using separate IOSGLContext objects (cla: yes)

11799 Let java unit tests build with autoninja (cla: yes)

11802 Adjust iOS frame start times to match the platform info (cla: yes)

11804 Incorporate View.setSystemGestureExclusionRects code review feedback from #11441 (cla: yes, platform-android)

11807 Fix deleting Thai vowel bug on iOS (cla: yes)

11808 Annotate nullability on FlutterEngine to make swift writing more ergonomic (cla: yes)

11817 Smooth out iOS irregular input events delivery (cla: yes)

11828 [Windows] Address #36422 by adding a context for async resource uploading (affects: desktop, cla: yes, platform-windows)