[libdazzle] menu-button: check for valid pointer

[Christian Hergert <chergert src gnome org>]

commit f90e1a42721a58ee48ed1ef5f867aedad744b5a6
Author: Christian Hergert <chergert redhat com>
Date:   Mon Jul 10 16:03:33 2017 -0700

    menu-button: check for valid pointer
    
    This can be NULL, so check it first.

 src/menus/dzl-menu-button-item.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/menus/dzl-menu-button-item.c b/src/menus/dzl-menu-button-item.c
index da8e593..420ae67 100644
--- a/src/menus/dzl-menu-button-item.c
+++ b/src/menus/dzl-menu-button-item.c
@@ -116,7 +116,7 @@ dzl_menu_button_item_notify_action_name (DzlMenuButtonItem *self,
   if (action_name)
     parts = g_strsplit (action_name, ".", 2);
 
-  if (parts[0] && parts[1])
+  if (parts && parts[0] && parts[1])
     draw = action_is_stateful (GTK_WIDGET (self), parts[0], parts[1]);
 
   g_object_set (self, "draw-indicator", draw, NULL);