Fix bug: Footer is not shown correct in the grid view

src/com/owncloud/android/ui/fragment/ExtendedListFragment.java

@@ -91,6 +91,7 @@ implements OnItemClickListener, OnEnforceableRefreshListener {
     
     protected void switchImageView(){
        imageView.setNumColumns(GridView.AUTO_FIT);
+       imageView.invalidateRowHeight();  // Force to recalculate mRowHeight of imageView
        imageView.invalidate();
     }