Crash less

BUG: 216908

svn path=/trunk/KDE/kdebase/workspace/; revision=1056931

scene.cpp

@@ -482,7 +482,7 @@ WindowQuadList Scene::Window::buildQuads( bool force ) const
         {
         Client *client = dynamic_cast<Client*>( toplevel );
         QRegion contents = clientShape();
-        QRegion center = client->transparentRect();
+        QRegion center = toplevel->transparentRect();
         QRegion decoration = (client && Workspace::self()->decorationHasAlpha() ?
                               QRegion(client->decorationRect()) : shape()) - center;
         ret = makeQuads( WindowQuadContents, contents );