46639 [flutter_tool] Prevent accidental calls to io.exit in unit tests (cla: yes, tool)

46640 install goldctl in docker build (cla: yes, team, waiting for tree to go green)

46643 [flutter_tool] Ensure dependency constraint for templates created with a driver test are correct (cla: yes, tool)

46645 Roll engine a614c0a2d45f..b9080c92b98a (1 commits) (autoroller: commit, cla: yes)

46647 Add UniqueKey documentation regarding const constructor (cla: yes, d: api docs, framework)

46648 Fix InputDecorator.isDense typo from true -> false (cla: yes, d: api docs, f: material design, framework)