Added HostListApl implementation to connect to legacy directory and GCD.

remoting/webapp/crd/js/legacy_host_list_api.js

Index: remoting/webapp/crd/js/legacy_host_list_api.js
diff --git a/remoting/webapp/crd/js/legacy_host_list_api.js b/remoting/webapp/crd/js/legacy_host_list_api.js
index c99c97758b1575ebfa76d5802694c7b493e4a4ad..c9941a6c6c65e75ef78b95a5d715db2b7f10da1f 100644
--- a/remoting/webapp/crd/js/legacy_host_list_api.js
+++ b/remoting/webapp/crd/js/legacy_host_list_api.js
@@ -25,6 +25,22 @@ remoting.LegacyHostListApi = function() {
 remoting.LegacyHostListApi.prototype.register = function(
     hostName, publicKey, hostClientId) {
   var newHostId = base.generateUuid();
+  return remoting.LegacyHostListApi.registerWithHostId(
+      newHostId, hostName, publicKey, hostClientId);

[John Williams, 2015/06/29 19:45:05]

I split the implementation of this method into a separate static method so it
can be called from CombinedHostListApi.

+};
+
+/**
+ * Registers a host with the Chromoting directory using a specified
+ * host ID, which should not be equal to the ID of any existing host.
+ *
+ * @param {string} newHostId The host ID of the new host.
+ * @param {string} hostName The user-visible name of the new host.
+ * @param {string} publicKey The public half of the host's key pair.
+ * @param {?string} hostClientId The OAuth2 client ID of the host.
+ * @return {!Promise<remoting.HostListApi.RegisterResult>}
+ */
+remoting.LegacyHostListApi.registerWithHostId = function(
+    newHostId, hostName, publicKey, hostClientId) {
   var newHostDetails = { data: {
     hostId: newHostId,
     hostName: hostName,
@@ -195,4 +211,9 @@ remoting.LegacyHostListApi.prototype.getSupportHost = function(supportId) {
   });
 };
 
+/** @override */
+remoting.LegacyHostListApi.prototype.getHostIdFromConfig = function(config) {
+  return base.getStringAttr(config, 'host_id');
+};
+
 })();