Fixing crash with invalid current page.

Change-Id: I36e76176b6172a747a6526d96b82c9870b56067c

src/com/android/launcher3/PagedView.java

@@ -515,7 +515,7 @@ public abstract class PagedView extends ViewGroup implements ViewGroup.OnHierarc
      * re-enable scrolling.
      */
     void stopScrolling() {
-        mCurrentPage = mNextPage;
+        mCurrentPage = getNextPage();
         forceFinishScroller();
     }