Don't dismiss volume during animation

(sometimes this messes up the state and results in it getting
stuck on the screen)

Bug: 22169656
Change-Id: I7738be8f7f54fc72d68bf9831baed2821f362bb1

packages/SystemUI/src/com/android/systemui/volume/VolumeDialog.java

@@ -462,6 +462,9 @@ public class VolumeDialog {
     }
 
     protected void dismissH(int reason) {
+        if (mMotion.isAnimating()) {
+            return;
+        }
         mHandler.removeMessages(H.DISMISS);
         mHandler.removeMessages(H.SHOW);
         if (!mShowing) return;