Attempt to fix crash on workspace drag and drop on certain JB devices

issue 13801679

Change-Id: I4769220ddeab566a869050b20d6064809c70bc19
diff --git a/src/com/android/launcher3/DragLayer.java b/src/com/android/launcher3/DragLayer.java
index 7ccbe6b..bbf8c8c 100644
--- a/src/com/android/launcher3/DragLayer.java
+++ b/src/com/android/launcher3/DragLayer.java
@@ -736,7 +736,13 @@
             mDropAnim.cancel();
         }
         if (mDropView != null) {
-            mDragController.onDeferredEndDrag(mDropView);
+            final DragView dropView = mDropView;
+            post(new Runnable() {
+                @Override
+                public void run() {
+                    mDragController.onDeferredEndDrag(dropView);
+                }
+            });
         }
         mDropView = null;
         invalidate();