57736 [AppBarTheme] adds centerTitle property (cla: yes, f: material design, framework, severe: new feature, waiting for tree to go green)

59405 [AppBar] adds toolbarHeight property to customize AppBar height (cla: yes, f: material design, f: scrolling, framework, severe: new feature, waiting for tree to go green)

perf: memory - 4 pull request(s)

50111 fix memory leak of android view (a: platform-views, cla: yes, p: framework, perf: memory, platform-android, plugin, waiting for tree to go green)

55486 Add DevTools memory test (cla: yes, perf: memory, severe: performance, team, waiting for tree to go green)

58430 [flutter_driver] make timeline request in chunks (a: tests, cla: yes, framework, perf: memory)