Webapp changes to support third party authentication

remoting/webapp/oauth2.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.
 
 /**
  * @fileoverview
  * OAuth2 class that handles retrieval/storage of an OAuth2 token.
  *
  * Uses a content script to trampoline the OAuth redirect page back into the
  * extension context.  This works around the lack of native support for
@@ skipping 290 matching lines @@
     'refresh_token': this.getRefreshToken_(),
     'grant_type': 'refresh_token'
   };
 
   remoting.xhr.post(this.getOAuth2TokenEndpoint_(),
                     this.processTokenResponse_.bind(this, onDone),
                     parameters);
 };
 
 /**
- * @private
- * @return {string} A URL-Safe Base64-encoded 128-bit random value. */
-remoting.OAuth2.prototype.generateXsrfToken_ = function() {
-  var random = new Uint8Array(16);
-  window.crypto.getRandomValues(random);
-  var base64Token = window.btoa(String.fromCharCode.apply(null, random));
-  return base64Token.replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
-};
-
-/**
  * Redirect page to get a new OAuth2 Refresh Token.
  *
  * @return {void} Nothing.
  */
 remoting.OAuth2.prototype.doAuthRedirect = function() {
-  var xsrf_token = this.generateXsrfToken_();
+  var xsrf_token = remoting.generateXsrfToken();
   window.localStorage.setItem(this.KEY_XSRF_TOKEN_, xsrf_token);
   var GET_CODE_URL = this.getOAuth2AuthEndpoint_() + '?' +
     remoting.xhr.urlencodeParamHash({
           'client_id': this.getClientId_(),
           'redirect_uri': this.getRedirectUri_(),
           'scope': this.SCOPE_,
           'state': xsrf_token,
           'response_type': 'code',
           'access_type': 'offline',
           'approval_prompt': 'force'
@@ skipping 186 matching lines @@
  * @return {?string} The email address, if it has been cached by a previous call
  *     to getEmail, otherwise null.
  */
 remoting.OAuth2.prototype.getCachedEmail = function() {
   var value = window.localStorage.getItem(this.KEY_EMAIL_);
   if (typeof value == 'string') {
     return value;
   }
   return null;
 };