static void
on_gtk_application_id_changed (MetaWindow  *window,
                               GParamSpec  *pspec,
                               gpointer     user_data)
{
  CinnamonWindowTracker *self = CINNAMON_WINDOW_TRACKER (user_data);
  tracked_window_changed (self, window);
}
static void
on_gtk_application_id_changed (MetaWindow  *window,
                               GParamSpec  *pspec,
                               gpointer     user_data)
{
  ShellWindowTracker *self = SHELL_WINDOW_TRACKER (user_data);
  tracked_window_changed (self, window);
}