65695 Fix FormFieldState value not in sync with the onChanged value from TextFormField. (cla: yes, f: material design, framework)

65787 Flutter Stable Framework Cherrypicks 1.20.4 (a: internationalization, cla: yes, d: examples, engine, f: material design, framework, team, tool)

65832 fix issue #55400 PopupMenuButton positions menu incorrectly with nest… (cla: yes, f: material design, framework, waiting for tree to go green)

65877 Update Navigation Rail test with regression comment and cleaner size checking (cla: yes, f: material design, framework, waiting for tree to go green)

65915 Fix DropdownButton bug (cla: yes, f: material design, framework, waiting for tree to go green)