我基本上想用ES6风格编写以下代码。listeners:{'neon-animation-finish':'_onNeonAnimationFinish'},我曾尝试使用如下属性，但从未触发_onNeonAnimationFinish回调。classMyElement{getbehaviors(){return[Polymer.NeonAnimationRunnerBehavior];}beforeRegister(){this.is='my-element';this.properties={name:{type:String}};this.listeners={'neon-anim