Added HostListApl implementation to connect to legacy directory and GCD.

remoting/webapp/crd/js/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
  * API for host-list management.
  */
 
 /** @suppress {duplicate} */
@@ skipping 53 matching lines @@
  * Attempts to look up a host using an ID derived from its publicly
  * visible access code.
  *
  * @param {string} supportId The support ID of the host to connect to.
  * @return {!Promise<!remoting.Host>}
  */
 remoting.HostListApi.prototype.getSupportHost = function(supportId) {
 };
 
 /**
+ * Get the host ID from the contents of a host config file.
+ *
+ * @param {!Object} config
+ * @return {string}
+ */
+remoting.HostListApi.prototype.getHostIdFromConfig = function(config) {
+};
+
+/**
  * @private {remoting.HostListApi}
  */
 var instance = null;
 
 /**
  * @return {!remoting.HostListApi}
  */
 remoting.HostListApi.getInstance = function() {
   if (instance == null) {
-    instance = remoting.settings.USE_GCD ?
-        new remoting.GcdHostListApi() :
-        new remoting.LegacyHostListApi();
+    if (remoting.settings.USE_GCD) {
+      var gcdInstance = new remoting.GcdHostListApi();
+      var legacyInstance = new remoting.LegacyHostListApi();
+      instance = new remoting.CombinedHostListApi(legacyInstance, gcdInstance);
+    } else {
+      instance = new remoting.LegacyHostListApi();
+    }
   }
   return instance;
 };
 
 /**
  * For testing.
  * @param {remoting.HostListApi} newInstance
  */
 remoting.HostListApi.setInstance = function(newInstance) {
   instance = newInstance;
@@ skipping 20 matching lines @@
  *     registrations in GCD.
  *
  * @typedef {{
  *   authCode: string,
  *   email: string,
  *   hostId: string,
  *   isLegacy: boolean
  * }}
  */
 remoting.HostListApi.RegisterResult;