HierarchyObserver 2478 ui/aura/window_unittest.cc   DISALLOW_COPY_AND_ASSIGN(HierarchyObserver);
HierarchyObserver 2485 ui/aura/window_unittest.cc     HierarchyObserver oroot(root_window());
HierarchyObserver 2488 ui/aura/window_unittest.cc     HierarchyObserver o1(w1.get());
HierarchyObserver 2532 ui/aura/window_unittest.cc     HierarchyObserver o(root_window());
HierarchyObserver 2592 ui/aura/window_unittest.cc     HierarchyObserver o(root_window());