Event.clone()メソッドのオーバーライドが必要な状況を確かめる

/**
 * Copyright yun ( http://wonderfl.net/user/yun )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/7fVt
 */

package {
    import flash.display.Sprite;
    import flash.events.EventDispatcher;
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    public class Test extends Sprite {
        private var _txt:TextField = new TextField();
        public function Test() {
            addChild(_txt);
            _txt.autoSize = TextFieldAutoSize.LEFT;
            _txt.wordWrap = true;
            var myEvent:TestEvent = new TestEvent("test");    // カスタムイベントのインスタンスを生成
            addEventListener("test", listener);
            dispatchEvent(myEvent);    // イベント配信
            dispatchEvent(myEvent);    // イベント配信            
        }
        private function listener(eventObject:TestEvent):void {
            _txt.appendText(eventObject.toString());
        }
    }
}
import flash.events.Event;
class TestEvent extends Event {
    public function TestEvent(event_str:String) {
        super(event_str);
    }
    /*override public function clone():Event {
        return new TestEvent(type);
    }*/
}