Updated XHR API so call sites are more descriptive.

remoting/webapp/crd/js/host_list_api_impl.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
  * REST API for host-list management.
  */
 
 'use strict';
 
 /** @suppress {duplicate} */
 var remoting = remoting || {};
 
 /**
  * @constructor
  * @implements {remoting.HostListApi}
  */
 remoting.HostListApiImpl = function() {
 };
 
 /**
  * Fetch the list of hosts for a user.
  *
  * @param {function(Array<remoting.Host>):void} onDone
  * @param {function(!remoting.Error):void} onError
  */
 remoting.HostListApiImpl.prototype.get = function(onDone, onError) {
-  /** @type {function(XMLHttpRequest):void} */
+  /** @type {function(remoting.Xhr.Response):void} */
   var parseHostListResponse =
       this.parseHostListResponse_.bind(this, onDone, onError);
   /** @param {string} token */
   var onToken = function(token) {
-    remoting.xhr.start({
+    new remoting.Xhr({
       method: 'GET',
       url: remoting.settings.DIRECTORY_API_BASE_URL + '/@me/hosts',
-      onDone: parseHostListResponse,
       oauthToken: token
-    });
+    }).then(parseHostListResponse);
   };
   remoting.identity.getToken().then(onToken, remoting.Error.handler(onError));
 };
 
 /**
  * Update the information for a host.
  *
  * @param {function():void} onDone
  * @param {function(!remoting.Error):void} onError
  * @param {string} hostId
  * @param {string} hostName
  * @param {string} hostPublicKey
  */
 remoting.HostListApiImpl.prototype.put =
     function(hostId, hostName, hostPublicKey, onDone, onError) {
   /** @param {string} token */
   var onToken = function(token) {
     var newHostDetails = {
       'data': {
         'hostId': hostId,
         'hostName': hostName,
         'publicKey': hostPublicKey
       }
     };
-    remoting.xhr.start({
+    new remoting.Xhr({
       method: 'PUT',
       url: remoting.settings.DIRECTORY_API_BASE_URL + '/@me/hosts/' + hostId,
-      onDone: remoting.xhr.defaultResponse(onDone, onError),
       jsonContent: newHostDetails,
       oauthToken: token
-    });
+    }).then(remoting.Xhr.defaultResponse(onDone, onError));
   };
   remoting.identity.getToken().then(onToken, remoting.Error.handler(onError));
 };
 
 /**
  * Delete a host.
  *
  * @param {function():void} onDone
  * @param {function(!remoting.Error):void} onError
  * @param {string} hostId
  */
 remoting.HostListApiImpl.prototype.remove = function(hostId, onDone, onError) {
   /** @param {string} token */
   var onToken = function(token) {
-    remoting.xhr.start({
+    new remoting.Xhr({
       method: 'DELETE',
       url: remoting.settings.DIRECTORY_API_BASE_URL + '/@me/hosts/' + hostId,
-      onDone: remoting.xhr.defaultResponse(onDone, onError),
       oauthToken: token
-    });
+    }).then(remoting.Xhr.defaultResponse(onDone, onError));
   };
   remoting.identity.getToken().then(onToken, remoting.Error.handler(onError));
 };
 
 /**
  * Handle the results of the host list request.  A success response will
  * include a JSON-encoded list of host descriptions, which is parsed and
  * passed to the callback.
  *
  * @param {function(Array<remoting.Host>):void} onDone
  * @param {function(!remoting.Error):void} onError
- * @param {XMLHttpRequest} xhr
+ * @param {remoting.Xhr.Response} xhrr
  * @private
  */
 remoting.HostListApiImpl.prototype.parseHostListResponse_ =
-    function(onDone, onError, xhr) {
-  if (xhr.status == 200) {
+    function(onDone, onError, xhrr) {
+  if (xhrr.status == 200) {
     var response = /** @type {{data: {items: Array}}} */
-        (base.jsonParseSafe(xhr.responseText));
+        (base.jsonParseSafe(xhrr.responseText));
     if (!response || !response.data) {
       console.error('Invalid "hosts" response from server.');
       onError(remoting.Error.UNEXPECTED);
     } else {
       var items = response.data.items || [];
       var hosts = items.map(
         function(/** Object */ item) {
           var host = new remoting.Host();
           host.hostName = getStringAttr(item, 'hostName', '');
           host.hostId = getStringAttr(item, 'hostId', '');
           host.status = getStringAttr(item, 'status', '');
           host.jabberId = getStringAttr(item, 'jabberId', '');
           host.publicKey = getStringAttr(item, 'publicKey', '');
           host.hostVersion = getStringAttr(item, 'hostVersion', '');
           host.tokenUrlPatterns = getArrayAttr(item, 'tokenUrlPatterns', []);
           host.updatedTime = getStringAttr(item, 'updatedTime', '');
           host.hostOfflineReason = getStringAttr(item, 'hostOfflineReason', '');
           return host;
       });
       onDone(hosts);
     }
   } else {
-    onError(remoting.Error.fromHttpStatus(xhr.status));
+    onError(remoting.Error.fromHttpStatus(xhrr.status));
   }
 };
 
 /** @type {remoting.HostListApi} */
 remoting.hostListApi = new remoting.HostListApiImpl();