Summary:
The logic was a little outdated to when we were accumulating subtrees, now its much simpler, if the previously focused id is not in the new frame, remove focus
Changelog: UIDebugger, fix focus mode behaviour
Reviewed By: mweststrate
Differential Revision: D45523026
fbshipit-source-id: 894a85df21cc27eb57dbef411ae57743d0c4f753