static void
on_focus_window_changed (MetaDisplay        *display,
                         GParamSpec         *spec,
                         CinnamonWindowTracker *tracker)
{
  update_focus_app (tracker);
}
static void
tracked_window_changed (CinnamonWindowTracker *self,
                        MetaWindow         *window)
{
  /* It's simplest to just treat this as a remove + add. */
  disassociate_window (self, window);
  track_window (self, window);
  /* also just recalculate the focused app, in case it was the focused
     window that changed */
  update_focus_app (self);
}
static void
on_wm_class_changed (MetaWindow  *window,
                     GParamSpec  *pspec,
                     gpointer     user_data)
{
  ShellWindowTracker *self = SHELL_WINDOW_TRACKER (user_data);

  /* It's simplest to just treat this as a remove + add. */
  disassociate_window (self, window);
  track_window (self, window);
  /* also just recaulcuate the focused app, in case it was the focused
     window that changed */
  update_focus_app (self);
}