Include activity reparent in transition

When an activity is reparented from a Task to a TaskFragment of
different bounds, freeze the surface and include it in app transition.

Bug: 196173550
Test: test with demo app
Test: AppTransitionTests#testActivityRecordReparentToTaskFragment
Change-Id: I73edc2c4091f0e4156ecf963ce4d1fcbd00333c8