Remove WebChannel's dependency on native EventTartget and its implementation of addEventListener and removeEventListener

RELNOTES: N/A

PiperOrigin-RevId: 329742032

Author: Closure Team

closure/goog/labs/net/webchannel.js

@@ -47,7 +47,6 @@ goog.require('goog.net.XmlHttpFactory');
  * to be enabled.
  *
  * @interface
- * @extends {EventTarget}
  * @extends {goog.events.Listenable}
  */
 goog.net.WebChannel = function() {};

closure/goog/labs/net/webchannel/webchannelbasetransport.js

@@ -192,31 +192,6 @@ WebChannelBaseTransport.Channel = function(url, opt_options) {
 goog.inherits(WebChannelBaseTransport.Channel, goog.events.EventTarget);
 
 
-/**
- * @override
- * @suppress {checkTypes}
- */
-WebChannelBaseTransport.Channel.prototype.addEventListener = function(
-    type, handler, /** boolean= */ opt_capture, opt_handlerScope) {
-  'use strict';
-  WebChannelBaseTransport.Channel.base(
-      this, 'addEventListener', type, handler, opt_capture, opt_handlerScope);
-};
-
-
-/**
- * @override
- * @suppress {checkTypes}
- */
-WebChannelBaseTransport.Channel.prototype.removeEventListener = function(
-    type, handler, /** boolean= */ opt_capture, opt_handlerScope) {
-  'use strict';
-  WebChannelBaseTransport.Channel.base(
-      this, 'removeEventListener', type, handler, opt_capture,
-      opt_handlerScope);
-};
-
-
 /**
  * @override
  */