[gtk+] a11y: Fix crash in notebook

[Benjamin Otte <otte src gnome org>]

commit 7b5b678e2e69f2b7000a451f6a2ae3bab294d19a
Author: Benjamin Otte <otte redhat com>
Date:   Sun Dec 18 17:14:47 2011 +0100

    a11y: Fix crash in notebook
    
    When the accessible was disposed before the notebook it referenced, the
    weak ref could still trigger. This works around it.

 gtk/a11y/gtknotebookaccessible.c |   15 ++-------------
 1 files changed, 2 insertions(+), 13 deletions(-)
---
diff --git a/gtk/a11y/gtknotebookaccessible.c b/gtk/a11y/gtknotebookaccessible.c
index c4e5b26..96e9cfe 100644
--- a/gtk/a11y/gtknotebookaccessible.c
+++ b/gtk/a11y/gtknotebookaccessible.c
@@ -42,6 +42,8 @@ check_focus_tab (gpointer data)
   atk_obj = ATK_OBJECT (data);
   accessible = GTK_NOTEBOOK_ACCESSIBLE (atk_obj);
   widget = gtk_accessible_get_widget (GTK_ACCESSIBLE (atk_obj));
+  if (widget == NULL)
+    return FALSE;
   notebook = GTK_NOTEBOOK (widget);
 
   accessible->idle_focus_id = 0;
@@ -133,17 +135,6 @@ page_removed_cb (GtkNotebook *notebook,
 
 
 static void
-accessible_destroyed (gpointer data)
-{
-  GtkNotebookAccessible *accessible = GTK_NOTEBOOK_ACCESSIBLE (data);
-
-  if (accessible->idle_focus_id)
-    {
-      g_source_remove (accessible->idle_focus_id);
-      accessible->idle_focus_id = 0;
-    }
-}
-static void
 gtk_notebook_accessible_initialize (AtkObject *obj,
                                     gpointer   data)
 {
@@ -171,8 +162,6 @@ gtk_notebook_accessible_initialize (AtkObject *obj,
   g_signal_connect (notebook, "page-removed",
                     G_CALLBACK (page_removed_cb), NULL);
 
-  g_object_weak_ref (G_OBJECT (notebook), (GWeakNotify)accessible_destroyed, obj);
-
   obj->role = ATK_ROLE_PAGE_TAB_LIST;
 }