Added HostListApl implementation to connect to legacy directory and GCD.

remoting/webapp/crd/js/host_controller.js

 // Copyright (c) 2012 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 || {};
 
 /** @constructor */
@@ skipping 334 matching lines @@
         onConfigUpdated, remoting.Error.handler(onError));
   }
 
   /** @param {Object} config */
   function onConfig(config) {
     if (!isHostConfigValid_(config)) {
       onError(remoting.Error.unexpected());
       return;
     }
     /** @type {string} */
-    var hostId = config['host_id'];
+    var hostId = base.getStringAttr(config, 'host_id');
     that.hostDaemonFacade_.getPinHash(hostId, newPin).then(
         updateDaemonConfigWithHash, remoting.Error.handler(onError));
   }
 
   // TODO(sergeyu): When crbug.com/121518 is fixed: replace this call
   // with an unprivileged version if that is necessary.
   this.hostDaemonFacade_.getDaemonConfig().then(
       onConfig, remoting.Error.handler(onError));
 };
 
@@ skipping 126 matching lines @@
     emailPromise.then(function(/** string */ email) {
       signalStrategy.connect(remoting.settings.XMPP_SERVER, email, token);
     });
   });
 
   return result;
 };
 
 /** @type {remoting.HostController} */
 remoting.hostController = null;