toolbar: Fix widget path creation code

- Ensure arrow button is always included
- Invalidate list when direction changes

gtk/gtkcontainerprivate.h

@@ -23,6 +23,7 @@
 G_BEGIN_DECLS
 
 
+GList *  _gtk_container_get_all_children       (GtkContainer *container);
 void     _gtk_container_queue_resize           (GtkContainer *container);
 void     _gtk_container_resize_invalidate      (GtkContainer *container);
 void     _gtk_container_clear_resize_widgets   (GtkContainer *container);