[pygtk] Make gtk.MenuItem.set_submenu accept None

[Paul Pogonyshev <paulp src gnome org>]

commit 25a126afb27e7f946a0da2fd8d304c99fa6c8ee6
Author: Paul Pogonyshev <pogonyshev gmx net>
Date:   Fri May 8 23:42:06 2009 +0300

    Make gtk.MenuItem.set_submenu accept None
    
    Fixes bug #534675.
---
 gtk/gtk-base.defs |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/gtk/gtk-base.defs b/gtk/gtk-base.defs
index 7daf5c9..cd8feda 100644
--- a/gtk/gtk-base.defs
+++ b/gtk/gtk-base.defs
@@ -12733,7 +12733,7 @@
   (c-name "gtk_menu_item_set_submenu")
   (return-type "none")
   (parameters
-    '("GtkWidget*" "submenu")
+    '("GtkWidget*" "submenu" (null-ok))
   )
 )