flutter#29708 Cupertino localization step 5: add french arb as translated example

flutter#29767: Cupertino localization step 6: add a GlobalCupertinoLocalizations base class with date time formatting

flutter#30527: Cupertino localization step 11: add more translation clarifications in the instructions

flutter#28629: Make sure everything in the Cupertino page transition can be linear when back swiping

flutter#28001: CupertinoTextField: added ability to change placeholder color

flutter#29304: Include platformViewId in semantics tree for iOS

flutter#29946: Let CupertinoPageScaffold have tap status bar to scroll to top

flutter#29474: Let CupertinoTextField’s clear button also call onChanged

flutter#29008: Update CupertinoTextField