AppOpsService: Fix another possible deadlock

* A possible race condition with the isInteractive() calls
  can result in a deadlock resulting in a soft reboot
* Use a broadcast receiver instead and listen for screen
  state changes
* Use AppOpsService.this for the synchronized part,
  otherwise the lock is essentially useless.
* Move the assignment of mIsInteractive into the lock so it
  is also synchronized
* Idea by Danny Baumann <dannybaumann@web.de>

Change-Id: I3c5a70cf67c3d0b3b9855a598d3d29e17c1aaedc