Fix activity move between displays

1. ActivityConfigCallback might not have been registered
because DecorView was not yet attached to window and ViewRootImpl
was not available. In this CL the callback is set as soon as a
DecorView is attached to window.
2. When private display was removed from system, its stacks were
moved to bottom in AM but moved to top in WM.
3. When reparenting stack visibility of activities should be updated
before reparenting in WM, because otherwise WM will be resizing
windows that should no longer visible and reporting it to clients.

Bug: 34164473
Test: android.server.cts.ActivityManagerDisplayTests
Test: #testOnMovedToDisplayCallback
Test: #testContentDestroyOnDisplayRemoved
Change-Id: I6ccc27d873d0d60d7650659fb25cbfcaaeb0fd07