Added a 'deferred' parameter on executeRunnableDismissingKeyguard().

OnDismissAction() should return true only when the dismiss should be
deferred, but the annonymous class on
executeRunnableDismissingKeyguard() was always return true, which was
cause a janky timeout when the runnable didn't launch an activity.

BUG: 28303552

Change-Id: I1f9e299102d6cebba44794c026a69cf43ea06990