IAppOpsCallback has weak reference to PlayerBase

The implementation of the IAppOpsCallback interface was an inner class
  that implicitly held a strong reference to the PlayerBase
  instance, preventing subclasses of PlayerBase to be GC'd.
The fix consists in making the IAppOpsCallback implementation be a static
  class and hold a weak reference to PlayerBase.

Test: see bug
Bug: 35359144

Change-Id: Ic97d07dad0be2376eef160d01ff4e4a9e5ee0bcd