[four-in-a-row] Use a header bar on the preferences dialog

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 30a035ca11383141ad4b093e0fb715cb06d22e58
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Sun May 11 17:08:37 2014 -0500

    Use a header bar on the preferences dialog

 src/prefs.c |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)
---
diff --git a/src/prefs.c b/src/prefs.c
index 411df84..4b69d2f 100644
--- a/src/prefs.c
+++ b/src/prefs.c
@@ -170,9 +170,8 @@ prefsbox_open (void)
 
   prefsbox = gtk_dialog_new_with_buttons (_("Preferences"),
                                          GTK_WINDOW (window),
-                                         GTK_DIALOG_DESTROY_WITH_PARENT,
-                                         GTK_STOCK_CLOSE,
-                                         GTK_RESPONSE_ACCEPT, NULL);
+                                         GTK_DIALOG_USE_HEADER_BAR,
+                                         NULL);
   gtk_container_set_border_width (GTK_CONTAINER (prefsbox), 5);
   gtk_box_set_spacing (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (prefsbox))),
                       2);