Finish rotation controller if the pending change is gone

Such when DisplayContent#getOrientation returns different values that
triggers rotation change A->B->A in a short time. The A->B will start
the rotation controller, but before the transition for A->B is started,
the later B->A restores to the original state, but there is no signal
to cancel the controller, which causes some windows to be hidden
(prepared to apply display change transition).

Fix: 289657013
Test: atest DisplayContentTests#testShellTransitRotation

Change-Id: I8d0e5bd07414f39fb8aca7cf33a01dcf0ae7956e