[gtk+] GtkBuilder: don't leak callbacks

[Matthias Clasen <matthiasc src gnome org>]

commit 5707e81c81de65af7b63ccf8529fc394e9f2b325
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Jun 15 23:33:51 2013 -0400

    GtkBuilder: don't leak callbacks
    
    This was noticed while running the testsuite under valgrind.

 gtk/gtkbuilder.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkbuilder.c b/gtk/gtkbuilder.c
index 326b5a1..7842565 100644
--- a/gtk/gtkbuilder.c
+++ b/gtk/gtkbuilder.c
@@ -343,6 +343,8 @@ gtk_builder_finalize (GObject *object)
   g_free (priv->resource_prefix);
   
   g_hash_table_destroy (priv->objects);
+  if (priv->callbacks)
+    g_hash_table_destroy (priv->callbacks);
 
   g_slist_foreach (priv->signals, (GFunc) _free_signal_info, NULL);
   g_slist_free (priv->signals);