62075 Update the About dialog to use the new button API. (cla: yes, f: material design, framework, waiting for tree to go green)

62076 [flutter_tools] switch cache mode to reload (cla: yes, tool, waiting for tree to go green)

62082 Mark flutter_gallery_ios__transition_perf flaky during investigation (cla: yes, platform-ios, team, team: flakes)

62083 Update the documentation of GlobalKey to explain why it is expensive (cla: yes, d: api docs, documentation, framework, waiting for tree to go green)

62085 Mark smoke_catalina_start_up_ios as not flaky (cla: yes, platform-ios, team, team: flakes, waiting for tree to go green)

62086 Add support for system alert sound (cla: yes, framework)