window: add a style class when we automatically create the titlebar

To distinguish it from custom titlebars added from applications.

https://bugzilla.gnome.org/show_bug.cgi?id=706592

diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index 18bcbc77ba9b7c177dd43683bf66f508cc1551ea..fec88e8e6ac87210c7889e6855c696c506afe917 100644 (file)
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -5273,6 +5273,7 @@ create_titlebar (GtkWindow *window)
                 NULL);
   context = gtk_widget_get_style_context (titlebar);
   gtk_style_context_add_class (context, GTK_STYLE_CLASS_TITLEBAR);
+  gtk_style_context_add_class (context, "default-decoration");
 
   title = g_markup_printf_escaped ("<b>%s</b>",
                                    priv->title ? priv->title : get_default_title ());