[gtk+] window: set GTK_STYLE_CLASS_TITLEBAR to custom titles

[Matthias Clasen <matthiasc src gnome org>]

commit 9896b9960dcbb26694c75f63d51e294c603610bc
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Fri Aug 16 19:26:12 2013 +0200

    window: set GTK_STYLE_CLASS_TITLEBAR to custom titles
    
    When a custom title is added to a GtkWindow, add the
    GTK_STYLE_CLASS_TITLEBAR to it, so the theme can apply the default rules
    for its style.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=706045

 gtk/gtkwindow.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index 5ea9b1d..df0ec26 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -3505,6 +3505,9 @@ gtk_window_set_titlebar (GtkWindow *window,
   if (visual)
     gtk_widget_set_visual (widget, visual);
 
+  gtk_style_context_add_class (gtk_widget_get_style_context (titlebar),
+                               GTK_STYLE_CLASS_TITLEBAR);
+
   gtk_widget_queue_resize (widget);
 }