clang-cl loplugin: bean

Change-Id: Iedaf2fc0c1e2cab446687c6c73cceb3c6b77e6e1
Reviewed-on: https://gerrit.libreoffice.org/29880
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

bean/native/win32/com_sun_star_comp_beans_LocalOfficeWindow.c

@@ -128,7 +128,7 @@ JNIEXPORT jlong JNICALL Java_com_sun_star_comp_beans_LocalOfficeWindow_getNative
        and calls on such construct produce
        a stack overflow.
      */
-    if (GetProp( hWnd, OLD_PROC_KEY )==0)
+    if (GetProp( hWnd, OLD_PROC_KEY )==NULL)
     {
         hFuncPtr = SetWindowLongPtr( hWnd, GWLP_WNDPROC, (LONG_PTR)OpenOfficeWndProc );
         SetProp( hWnd, OLD_PROC_KEY, (HANDLE)hFuncPtr );