Fix Fade out during Activity Transition.
Fix Fade out during Activity Transition.

Bug 22181705

The Fade Transition sets the transitionAlpha in onTransitionEnd.
I previously changed Visibility to only do it in onAnimationEnd,
so the onTransitionEnd overrides the Visibility's version. This
fixes that change.

Change-Id: I7df478897b6fcfec20999965e297925b65a1448b

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base