[gtk+] GtkHeaderBar: Add the titlebutton style to the close button

[Matthias Clasen <matthiasc src gnome org>]

commit 22378bbab56e49d9948e1ec2122bb6737f1543cc
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Aug 20 11:33:07 2013 -0400

    GtkHeaderBar: Add the titlebutton style to the close button
    
    This will let the theme unify the appearance of this button with
    the window buttons in 'traditional' title bars.

 gtk/gtkheaderbar.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkheaderbar.c b/gtk/gtkheaderbar.c
index 992f441..a421860 100644
--- a/gtk/gtkheaderbar.c
+++ b/gtk/gtkheaderbar.c
@@ -235,6 +235,7 @@ add_close_button (GtkHeaderBar *bar)
   gtk_widget_set_valign (button, GTK_ALIGN_CENTER);
   context = gtk_widget_get_style_context (button);
   gtk_style_context_add_class (context, "image-button");
+  gtk_style_context_add_class (context, "titlebutton");
   icon = g_themed_icon_new ("window-close-symbolic");
   image = gtk_image_new_from_gicon (icon, GTK_ICON_SIZE_MENU);
   g_object_unref (icon);