12218 Namespace patched SDK names to not conflict with Topaz (cla: yes)

12222 Do not generate kernel platform files on topaz tree (cla: yes)

12226 [web_ui] add missing dispose handler for MethodCalls to flutter/platform_view (cla: yes)

12227 [web_ui] PersistedPlatformView attribute update handling to enable resizing (cla: yes)

12228 pin and auto-install chrome version (cla: yes)

12229 Improve check to render (or not) a DRRect when inner falls outside of outer on RecordingCanvas (cla: yes)

12230 Add an initial macOS version of FlutterAppDelegate (cla: yes)

12232 FlutterViewController notify will dealloc (cla: yes)