[gtk+] GtkMenu: Add a separate style class to the toplevel of menus

[Matthias Clasen <matthiasc src gnome org>]

commit 3cf916be8af009b54e661c70c0d26c9c09c920dd
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Jun 6 19:06:15 2014 -0400

    GtkMenu: Add a separate style class to the toplevel of menus
    
    This is necessary in order to use .window-frame.csd.popup for
    styling csd menus.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=731187

 gtk/gtkmenu.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkmenu.c b/gtk/gtkmenu.c
index f1bf243..cb8d98e 100644
--- a/gtk/gtkmenu.c
+++ b/gtk/gtkmenu.c
@@ -1099,6 +1099,8 @@ gtk_menu_init (GtkMenu *menu)
   gtk_window_set_resizable (GTK_WINDOW (priv->toplevel), FALSE);
   gtk_window_set_mnemonic_modifier (GTK_WINDOW (priv->toplevel), 0);
 
+  gtk_style_context_add_class (gtk_widget_get_style_context (priv->toplevel), "popup");
+
   /* Refloat the menu, so that reference counting for the menu isn't
    * affected by it being a child of the toplevel
    */