Fix Activity Transition mess-up.

Bug 28610520

isTopOfTask() was returns false in onResume always because
it wasn't being made visible until after onResume. The visibility
of the window is not important for this method (older versions
didn't check it at all), so that was removed.

Change-Id: I45e506e72356cc3808e2e9340739726c99da7d97

core/java/android/app/Activity.java

@@ -5948,7 +5948,7 @@ public class Activity extends ContextThemeWrapper
      * @return true if this is the topmost, non-finishing activity in its task.
      */
     private boolean isTopOfTask() {
-        if (mToken == null || mWindow == null || !mWindowAdded) {
+        if (mToken == null || mWindow == null) {
             return false;
         }
         try {