remoting: Fix JSCompiler issues blocking ES6 transition.

remoting/webapp/base/js/error.js

 // Copyright 2013 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.
 
 'use strict';
 
 /** @suppress {duplicate} */
 var remoting = remoting || {};
 
 /**
@@ skipping 36 matching lines @@
  */
 remoting.Error.prototype.getDetail = function() {
   return this.detail_;
 };
 
 /**
  * Checks the type of an error.
  * @param {remoting.Error.Tag} tag
  * @param {...remoting.Error.Tag} var_args
  * @return {boolean} True if this object has one of the specified tags.
+ * @suppress {reportUnknownTypes}
  */
 remoting.Error.prototype.hasTag = function(tag, var_args) {
   var thisTag = this.tag_;
   return Array.prototype.some.call(
       arguments,
       function(/** remoting.Error.Tag */ tag) {
         return thisTag == tag;
       });
 };
 
@@ skipping 98 matching lines @@
 remoting.Error.handler = function(onError) {
   return function(/** * */ error) {
     if (error instanceof remoting.Error) {
       onError(/** @type {!remoting.Error} */ (error));
     } else {
       console.error('Unexpected error:', error);
       onError(remoting.Error.unexpected());
     }
   };
 };