code: function PostEmitter() {
  	var _this = this;
  	//might be global
  	this._listener = function(ev) {
  		//check origin
  		//then
  		var data = ev.data;
  		_this.emit.apply(_this, data instanceof Array ? data : [data]);
  	};
  	window[attach](prefix + 'message', this._listener);
  }
docs: PostEmitter constructor.
  Listen local and remote messages.
  
  @api public