[libdazzle] menu-button: add padding to class

[Christian Hergert <chergert src gnome org>]

commit 9adafa099db9f9c6c2f6bf77851ee7fbeb05a53c
Author: Christian Hergert <chergert redhat com>
Date:   Sun Jul 9 18:27:22 2017 -0700

    menu-button: add padding to class

 src/menus/dzl-menu-button.h |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/src/menus/dzl-menu-button.h b/src/menus/dzl-menu-button.h
index 3a94c96..d07d548 100644
--- a/src/menus/dzl-menu-button.h
+++ b/src/menus/dzl-menu-button.h
@@ -30,6 +30,11 @@ G_DECLARE_DERIVABLE_TYPE (DzlMenuButton, dzl_menu_button, DZL, MENU_BUTTON, GtkM
 struct _DzlMenuButtonClass
 {
   GtkMenuButtonClass parent_class;
+
+  gpointer _reserved1;
+  gpointer _reserved2;
+  gpointer _reserved3;
+  gpointer _reserved4;
 };
 
 GtkWidget     *dzl_menu_button_new_with_model  (const gchar   *icon_name,