Reverts: flutter/flutter#142942
Initiated by: zanderso
Reason for reverting: Seems to have affected iOS platform view focus: https://ci.chromium.org/ui/p/flutter/builders/prod/Mac_ios%20native_platform_view_ui_tests_ios/10626/overview
Original PR Author: gspencergoog
Reviewed By: {yjbanov, goderbauer, chunhtai}
This change reverts the following previous change:
## Description
This causes the `Focus` widget to request focus on its focus node if the accessibility system (screen reader) focuses a widget via the `SemanticsAction.focus` action.
## Related Issues
- https://github.com/flutter/flutter/issues/83809
## Tests
- Added a test to make sure that focus is requested when `SemanticsAction.focus` is sent by the engine.
ec9965bd89