Fixed a heads up crash

Some references to notifications were still
kept around while timing out, leading to small
leaks and sometimes crashes.

Bug: 22819475
Change-Id: I1429b5669366521c6374efbcae6c26d6e407d8cc

packages/SystemUI/src/com/android/systemui/statusbar/policy/HeadsUpManager.java

@@ -452,8 +452,8 @@ public class HeadsUpManager implements ViewTreeObserver.OnComputeInternalInsetsL
             for (NotificationData.Entry entry : mEntriesToRemoveAfterExpand) {
                 removeHeadsUpEntry(entry);
             }
-            mEntriesToRemoveAfterExpand.clear();
         }
+        mEntriesToRemoveAfterExpand.clear();
     }
 
     public void setTrackingHeadsUp(boolean trackingHeadsUp) {