Added (incomplete) implementation of HostListApi using GCD.

remoting/webapp/crd/js/mock_host_list_api.js

 // Copyright 2014 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
  * Mock implementation of remoting.HostList
  */
 
 'use strict';
@@ skipping 34 matching lines @@
       'updatedTime': new Date(1970, 1, 1).toISOString()
     }
   ];
 };
 
 /** @override */
 remoting.MockHostListApi.prototype.register = function(
     newHostId, hostName, publicKey, hostClientId) {
   if (this.registerResult === null) {
     return Promise.reject(
-        new remoting.Error(remoting.Error.Tag.REGISTRATION_FAILED));
+        new remoting.Error(
+            remoting.Error.Tag.REGISTRATION_FAILED,
+            'MockHostListApi.register'));
   } else {
     return Promise.resolve(this.registerResult);
   }
 };
 
 /** @override */
 remoting.MockHostListApi.prototype.get = function() {
   var that = this;
-  new Promise(function(resolve, reject) {
+  return new Promise(function(resolve, reject) {
     remoting.mockIdentity.validateTokenAndCall(
         resolve, remoting.Error.handler(reject), [that.hosts]);
   });
 };
 
-/** @override */
+/**
+ * @override
+ * @param {string} hostId
+ * @param {string} hostName
+ * @param {string} hostPublicKey
+ */
 remoting.MockHostListApi.prototype.put =
     function(hostId, hostName, hostPublicKey) {
   /** @type {remoting.MockHostListApi} */
   var that = this;
   return new Promise(function(resolve, reject) {
     var onTokenValid = function() {
       for (var i = 0; i < that.hosts.length; ++i) {
         var host = that.hosts[i];
         if (host.hostId == hostId) {
           host.hostName = hostName;
           host.hostPublicKey = hostPublicKey;
           resolve(undefined);
           return;
         }
       }
       console.error('PUT request for unknown host: ' + hostId +
                     ' (' + hostName + ')');
       reject(remoting.Error.unexpected());
     };
     remoting.mockIdentity.validateTokenAndCall(onTokenValid, reject, []);
   });
 };
 
-/** @override */
+/**
+ * @override
+ * @param {string} hostId
+ */
 remoting.MockHostListApi.prototype.remove = function(hostId) {
   /** @type {remoting.MockHostListApi} */
   var that = this;
   return new Promise(function(resolve, reject) {
     var onTokenValid = function() {
       for (var i = 0; i < that.hosts.length; ++i) {
         var host = that.hosts[i];
         if (host.hostId == hostId) {
           that.hosts.splice(i, 1);
           resolve(undefined);
           return;
         }
       }
       console.error('DELETE request for unknown host: ' + hostId);
       reject(remoting.Error.unexpected());
     };
     remoting.mockIdentity.validateTokenAndCall(onTokenValid, reject, []);
   });
 };
 
 /**
  * @param {boolean} active
  */
 remoting.MockHostListApi.setActive = function(active) {
-  remoting.hostListApi = active ? new remoting.MockHostListApi()
-                                : new remoting.HostListApiImpl();
+  remoting.HostListApi.setInstance(
+      active ? new remoting.MockHostListApi() : null);
 };