Messaging app ClassCastException (DecorContext -> Activity) when SMSoIMS is initiated

Bug 27649619

Change-Id: I1c0de7c14abd255ceb9d61a377db3276c32fede0
diff --git a/src/com/android/messaging/ui/animation/PopupTransitionAnimation.java b/src/com/android/messaging/ui/animation/PopupTransitionAnimation.java
index 21529c6..5fc2a19 100644
--- a/src/com/android/messaging/ui/animation/PopupTransitionAnimation.java
+++ b/src/com/android/messaging/ui/animation/PopupTransitionAnimation.java
@@ -79,8 +79,7 @@
         mDestRect = new Rect();
         mPopupRect = new Rect();
         mActionBarRect = new Rect();
-        final Activity activity = (Activity) viewToAnimate.getRootView().getContext();
-        mActionBarView = activity.getWindow().getDecorView().findViewById(
+        mActionBarView = viewToAnimate.getRootView().findViewById(
                 android.support.v7.appcompat.R.id.action_bar);
         mRectEvaluator = RectEvaluatorCompat.create();
         setDuration(UiUtils.MEDIAPICKER_TRANSITION_DURATION);