ivElement.prototype,decorate(){this.observer_=new MutationObserver(this.didMutate_.bind(this));this.observer_.observe(this,{childList:true});Object.defineProperty(this,'textContent',{get:undefined,set:this.onSetTextContent_});},appendChild(x){HTMLDivElement.prototype.appendChild.call(this,x);this.didMutate_(this.observer_.takeRecords());},insertBefore(x,y){HTMLDivElement.prototype.insertBefore.call(this,x,y);this.didMutate_(this.observer_.takeRecords());},removeChild(x){HTMLDivElement.prototype....