19860 Support talkback in hybrid composition (cla: yes, platform-android, waiting for tree to go green)

19864 1.20.0-7.2.pre: CP 12847e899e080104365f93843c25a3b3b5648895 (cla: yes, platform-android)

19871 Fix failing Dart analyzer checks in the web UI tests (cla: yes)

19895 Made the linter print out more information in its output and fixed bugs (cla: yes, platform-android)

19896 [windows] Separate the engine from the view (affects: desktop, cla: yes, platform-windows)

19898 [a11y-web] Semantics fix (cla: yes)