/**
  * @return ActionScheduler_QueueRunner
  * @codeCoverageIgnore
  */
 public static function instance()
 {
     if (empty(self::$admin_view)) {
         $class = apply_filters('action_scheduler_admin_view_class', 'ActionScheduler_AdminView');
         self::$admin_view = new $class();
     }
     return self::$admin_view;
 }