49572 revert #48985 (a: accessibility, a: internationalization, a: tests, cla: yes, d: examples, f: cupertino, f: material design, framework, team, team: gallery, tool, waiting for tree to go green)

49574 [Material] Create a Navigation Rail component and theme (cla: yes, f: material design, framework, waiting for tree to go green)

49575 [flutter_tool] Make base/net.dart context free (cla: yes, tool, waiting for tree to go green)

49577 [flutter_tools] remove alternative build aot code path (cla: yes, tool)

49581 Unmark tests as flaky because they are no longer flaky (cla: yes, team, team: infra)