GtkAssistant: Fix criticals on dispose

After the recent change thta introduced boxes between the pages
and the notebook, we were no longer careful enough when disposing
the assistant. Fix that up.

diff --git a/gtk/gtkassistant.c b/gtk/gtkassistant.c
index 3d989637d22f1743006757f889cb7ff796b6ae51..b6d2d82d6afca5328349f907a31c0b1835dc3138 100644 (file)
--- a/gtk/gtkassistant.c
+++ b/gtk/gtkassistant.c
@@ -1472,7 +1472,9 @@ gtk_assistant_remove (GtkContainer *container,
 
   /* Forward this removal to the content notebook */
   box = gtk_widget_get_parent (page);
-  if (gtk_widget_get_parent (box) == assistant->priv->content)
+  if (GTK_IS_BOX (box) &&
+      assistant->priv->content != NULL &&
+      gtk_widget_get_parent (box) == assistant->priv->content)
     {
       container = (GtkContainer *) assistant->priv->content;
       gtk_container_remove (container, box);