Only split update region into client and non-client parts if there actually
is something to split

reactos/subsys/win32k/ntuser

diff -u -r1.82 -r1.83
--- painting.c	10 May 2004 17:07:18 -0000	1.82
+++ painting.c	15 May 2004 08:01:56 -0000	1.83
@@ -16,7 +16,7 @@

  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  *

- *  $Id: painting.c,v 1.82 2004/05/10 17:07:18 weiden Exp $

+ *  $Id: painting.c,v 1.83 2004/05/15 08:01:56 gvg Exp $

  *
  *  COPYRIGHT:        See COPYING in the top level directory
  *  PROJECT:          ReactOS kernel

@@ -286,6 +286,7 @@

     * Split the nonclient update region.
     */
 

+   if (NULL != Window->UpdateRegion)

    {
       HRGN hRgnWindow, hRgnNonClient;