81312 [flutter_tools] remove mocks from test_compiler test (tool, cla: yes, waiting for tree to go green)

81324 allow flutterManifest to handle empty lists, add unit tests (tool, cla: yes, waiting for tree to go green)

81341 [flutter_tools] Always build test assets when running tests (tool, cla: yes)

81342 Remove Finder extended attributes before code signing iOS frameworks (platform-ios, tool, cla: yes, t: xcode)

81352 Replace MockAndroidDevice and MockIOSDevice with fakes (team, tool, cla: yes, waiting for tree to go green, a: null-safety)

81368 [flutter_tools] Show linux distribution and kernel release in flutter doctor (tool, cla: yes, waiting for tree to go green)