Disallow top-level navigation in gaia iframe

chrome/browser/resources/inline_login/inline_login.js

 // Copyright 2013 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 Inline login UI.
  */
 
 <include src="../gaia_auth_host/gaia_auth_host.js"></include>
 
@@ skipping 51 matching lines @@
 
   /**
    * Invoked when failed to get oauth2 refresh token.
    */
   function handleOAuth2TokenFailure() {
     // TODO(xiyuan): Show an error UI.
     authExtHost.reload();
     $('contents').classList.toggle('loading', true);
   }
 
+  /**
+   * Returns the auth host instance, for testing purpose.
+   */
+  function getAuthExtHost() {
+    return authExtHost;
+  }
+
   return {
+    getAuthExtHost: getAuthExtHost,
     initialize: initialize,
     loadAuthExtension: loadAuthExtension,
     closeDialog: closeDialog,
     handleOAuth2TokenFailure: handleOAuth2TokenFailure
   };
 });
 
 document.addEventListener('DOMContentLoaded', inline.login.initialize);