AAAPlugin cause NPE on hot reload

[greenlaw110]

Found in act-aaa-1.6.0

Error stack:

java.lang.NullPointerException: null
	at act.aaa.AAAPlugin$3.on(AAAPlugin.java:81)
	at act.aaa.AAAPlugin$3.on(AAAPlugin.java:75)
	at act.event.EventBus.callOn(EventBus.java:1440)
	at act.event.EventBus.callOn(EventBus.java:1462)
	at act.event.EventBus.callOn(EventBus.java:1497)
	at act.event.EventBus._emitWithOnceBus(EventBus.java:1413)
	at act.event.EventBus.emit(EventBus.java:975)
	at act.app.ActionContext.resolve(ActionContext.java:1336)
	at act.route.Router$ContextualHandler.handle(Router.java:1766)
	at act.xio.NetworkHandler$3.run(NetworkHandler.java:166)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)