Converted remoting.Error from an enum to a class

remoting/webapp/crd/js/xhr.js

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview
  * Simple utilities for making XHRs more pleasant.
  */
 
 'use strict';
@@ skipping 181 matching lines @@
   }
   xhr.withCredentials = withCredentials;
   xhr.send(content);
   return xhr;
 };
 
 /**
  * Generic success/failure response proxy.
  *
  * @param {function():void} onDone
- * @param {function(remoting.Error):void} onError
+ * @param {function(!remoting.Error):void} onError
  * @return {function(XMLHttpRequest):void}
  */
 remoting.xhr.defaultResponse = function(onDone, onError) {
   /** @param {XMLHttpRequest} xhr */
   var result = function(xhr) {
-    /** @type {remoting.Error} */
     var error =
         remoting.Error.fromHttpStatus(/** @type {number} */ (xhr.status));
-    if (error == remoting.Error.NONE) {
+    if (error.tag == remoting.Error.Tag.NONE) {
       onDone();
     } else {
       onError(error);
     }
   };
   return result;
 };