cros: Pass gaia_auth init params via postMessage.

chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.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.
 
 login.createScreen('OAuthEnrollmentScreen', 'oauth-enrollment', function() {
   /** @const */ var STEP_SIGNIN = 'signin';
   /** @const */ var STEP_WORKING = 'working';
   /** @const */ var STEP_ERROR = 'error';
   /** @const */ var STEP_SUCCESS = 'success';
 
   /** @const */ var HELP_TOPIC_ENROLLMENT = 4631259;
 
   return {
     EXTERNAL_API: [
       'showStep',
       'showError',
       'doReload',
     ],
 
     /**
      * URL to load in the sign in frame.
      */
     signInUrl_: null,
 
     /**
+     * Gaia auth params for sign in frame.
+     */
+    signInParams_: {},
+
+    /**
      * The current step. This is the last value passed to showStep().
      */
     currentStep_: null,
 
     /**
      * Opaque token used to correlate request and response while retrieving the
      * authenticated user's e-mail address from GAIA.
      */
     attemptToken_: null,
 
@@ skipping 89 matching lines @@
 
       return buttons;
     },
 
     /**
      * Event handler that is invoked just before the frame is shown.
      * @param {Object} data Screen init payload, contains the signin frame
      * URL.
      */
     onBeforeShow: function(data) {
-      var url = data.signin_url;
-      url += '?gaiaUrl=' + encodeURIComponent(data.gaiaUrl);
-      url += '&needPassword=0';
-      this.signInUrl_ = url;
+      this.signInParams_ = {};
+      this.signInParams_['gaiaUrl'] = data.gaiaUrl;
+      this.signInParams_['needPassword'] = false;
+      this.signInUrl_ = data.signin_url;
       var modes = ['manual', 'forced', 'recovery'];
       for (var i = 0; i < modes.length; ++i) {
         this.classList.toggle('mode-' + modes[i],
                               data.enrollment_mode == modes[i]);
       }
       this.managementDomain_ = data.management_domain;
-      $('oauth-enroll-signin-frame').contentWindow.location.href =
-          this.signInUrl_;
+      this.doReload();
       this.learnMoreHelpTopicID_ = data.learn_more_help_topic_id;
       this.updateLocalizedContent();
       this.showStep(STEP_SIGNIN);
     },
 
     /**
      * Cancels enrollment and drops the user back to the login screen.
      */
     cancel: function() {
       chrome.send('oauthEnrollClose', ['cancel']);
@@ skipping 23 matching lines @@
      * @param {string} message the error message.
      * @param {boolean} retry whether the retry link should be shown.
      */
     showError: function(message, retry) {
       $('oauth-enroll-error-message').textContent = message;
       $('oauth-enroll-error-retry').hidden = !retry;
       this.showStep(STEP_ERROR);
     },
 
     doReload: function() {
-      $('oauth-enroll-signin-frame').contentWindow.location.href =
-          this.signInUrl_;
+      var signInFrame = $('oauth-enroll-signin-frame');
+
+      var sendParamsOnLoad = function() {
+        signInFrame.removeEventListener('load', sendParamsOnLoad);
+        signInFrame.contentWindow.postMessage(this.signInParams_,
+            'chrome-extension://mfffpogegjflfpflabcdkioaeobkgjik');
+      }.bind(this);
+
+      signInFrame.addEventListener('load', sendParamsOnLoad);
+      signInFrame.contentWindow.location.href = this.signInUrl_;
     },
 
     /**
      * Retries the enrollment process after an error occurred in a previous
      * attempt. This goes to the C++ side through |chrome| first to clean up the
      * profile, so that the next attempt is performed with a clean state.
      */
     doRetry_: function() {
       chrome.send('oauthEnrollRetry');
     },
@@ skipping 64 matching lines @@
      * Opens the learn more help topic.
      */
     launchLearnMoreHelp_: function() {
       if (this.learnMoreHelpTopicID_) {
         chrome.send('launchHelpApp', [this.learnMoreHelpTopicID_]);
       }
     }
   };
 });