84166 Revert “Re-land “Migrate android_semantics_testing to null safety (#84136)”” (team, a: accessibility, cla: yes)

84476 Turn on avoid_dynamic_calls lint, except packages/flutter tests, make appropriate changes. (a: tests, team, tool, framework, f: material design, a: accessibility, a: internationalization, cla: yes, f: cupertino, d: examples)

84478 Turn on avoid_dynamic_calls lint in packages/flutter tests, make appropriate changes. (a: tests, team, tool, framework, f: material design, a: accessibility, a: internationalization, cla: yes, f: cupertino, d: examples, waiting for tree to go green)

84820 Audit devicelab log streaming for nullability (team, a: accessibility, cla: yes, waiting for tree to go green, a: null-safety)