48607 Avoid runtimeType.toString in toString overrides/debugLabels (cla: yes, f: material design, framework, team, waiting for tree to go green)

48610 [tools] Rename dev_finder to device-finder. (cla: yes, team, tool, waiting for tree to go green)

48611 Implement takeScreenshot and add driver test for Fuchsia (cla: yes, customer: fuchsia, team, tool, waiting for tree to go green)

48614 [flutter_tools] Removes the need of a no-op plugin implementations (cla: yes, team, tool, waiting for tree to go green)

48645 Roll engine 7ef88f85d572..3d37d39d95ad (2 commits) (autoroller: commit, cla: yes)