63412 Fix App.framework path in Podfile (a: existing-apps, cla: yes, platform-ios, team, tool, waiting for tree to go green)

63416 [flutter_tools] add –null-assertions flag for debugging with null safety (tool, waiting for tree to go green)

63433 Remove more timeouts (tool, waiting for tree to go green)

63446 [flutter_tools] add more error context to tree shaker failure (tool, waiting for tree to go green)

63505 Fix version parsing (cla: yes, tool)

63517 Move Android doctor SDK check to 29 and Cirrus images to 30 (a: accessibility, cla: yes, d: examples, team, tool)

63526 [flutter_tools] handle invalid yaml in plugin dependency (cla: yes, tool, waiting for tree to go green)