[nautilus] Fix crash when changing icon captions settings

[Cosimo Cecchi <cosimoc src gnome org>]

commit fc2daed9a9a36228870843bce2e708d61173c951
Author: Volker Sobek <reklov live com>
Date:   Sat Apr 19 21:01:23 2014 +0200

    Fix crash when changing icon captions settings
    
    Don't SIGSEGV when changing any of the three combo boxes in the
    preferences' Display tab. This issue existed since commit d8a8ab3.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=728503

 src/nautilus-file-management-properties.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)
---
diff --git a/src/nautilus-file-management-properties.c b/src/nautilus-file-management-properties.c
index c8bd964..33f4546 100644
--- a/src/nautilus-file-management-properties.c
+++ b/src/nautilus-file-management-properties.c
@@ -358,9 +358,11 @@ nautilus_file_management_properties_dialog_setup_icon_caption_page (GtkBuilder *
                create_icon_caption_combo_box_items (GTK_COMBO_BOX_TEXT (combo_box), columns);
                gtk_widget_set_sensitive (combo_box, writable);
 
-               g_signal_connect (combo_box, "changed",
-                                 G_CALLBACK (icon_captions_changed_callback),
-                                 builder);
+               g_signal_connect_data (combo_box, "changed",
+                                      G_CALLBACK (icon_captions_changed_callback),
+                                      g_object_ref (builder),
+                                      (GClosureNotify)g_object_unref,
+                                      0);
        }
 
        nautilus_column_list_free (columns);