Fixed a bug where the brighness mirror would make everything invisible

Because of some new animation optimization, this could lead to issues
where we weren't cancelling the animation in one side case.

Fixes: 156569031
Test: tap on brightness mirror, observe
Change-Id: I18164b16a612431f8b3ec87a5b5834c0f48dd761
(cherry picked from commit 7d9d378b283c03d8ccc5f35d1f18424ab36549e7)
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/PropertyAnimator.java b/packages/SystemUI/src/com/android/systemui/statusbar/notification/PropertyAnimator.java
index b1b6a1c..3517e24 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/PropertyAnimator.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/PropertyAnimator.java
@@ -92,6 +92,9 @@
         AnimatorListenerAdapter listener = properties.getAnimationFinishListener(property);
         if (currentValue.equals(newEndValue)) {
             // Skip the animation!
+            if (previousAnimator != null) {
+                previousAnimator.cancel();
+            }
             if (listener != null) {
                 listener.onAnimationEnd(null);
             }