36556 Fix usage test to use local usage (cla: yes, tool)

36560 [flutter_tools] Add some useful commands to the README.md (cla: yes, tool)

36564 Make sure fx flutter attach can find devices (cla: yes, tool)

36569 Some minor cleanup for flutter_tools (cla: yes, tool)

36570 Some minor fixes to the tool_coverage tool (cla: yes, tool)

36571 Some minor cleanup in devicelab (cla: yes, team)

36579 Add gradient text docs (a: typography, cla: yes, framework)

36585 Place build outputs under dart tool (cla: yes, tool)