Fix FTBFS with clang.

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>

kxmleditor/kxmleditorshell.h

@@ -24,7 +24,9 @@
 
 #include <tdeparts/mainwindow.h>
 
-class KParts::ReadWritePart;
+namespace KParts {
+    class ReadWritePart;
+}
 class KXMLEditorShellIface;
 class TDEAction;
 class KXEShellManager;