75866 added flutter_engine_group_performance to the prod_builders (cla: yes, team, waiting for tree to go green)

75871 [flutter_tools] remove package HTTP and add pub.dev head check tests (cla: yes, tool, waiting for tree to go green)

75873 Revert “Removed ButtonBar from AlertDialog” (cla: yes, f: material design, framework)

75888 All arguments must be documented. (cla: yes, team, tool, waiting for tree to go green)

75892 Mark flutter_engine_group_performance not flaky (cla: yes, team)

75893 Replace Gitter with Discord badge (cla: yes)

75894 Fix FocusManager constructor (a: tests, cla: yes, framework)