47837 Reland 39919 CupertinoPicker (cla: yes, f: cupertino, framework)

47845 Support preferred locales for gen_l10n (a: internationalization, cla: yes, severe: new feature, team, tool)

47846 Revert “Roll engine 42bb7c9eea9a..dc0187f21777 (15 commits) (#47829)” (cla: yes, engine)

47847 Roll engine dc0187f21777..69e41497404d (6 commits) (autoroller: commit, cla: yes)

47855 Reland “Add brightness to CupertinoNavigationBar (fixes #46216) (#47521)” (cla: yes, f: cupertino, framework, waiting for tree to go green)