Fix the data race of OobeTest.NewUser browser test and enable it.

chrome/browser/resources/chromeos/login/screen_gaia_signin.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 Oobe signin screen implementation.
  */
 
 cr.define('login', function() {
   // Gaia loading time after which error message must be displayed and
   // lazy portal check should be fired.
-  /** @const */ var GAIA_LOADING_PORTAL_SUSSPECT_TIME_SEC = 15;
+  /** @const */ var GAIA_LOADING_PORTAL_SUSSPECT_TIME_SEC = 7;
 
   // Maximum Gaia loading time in seconds.
   /** @const */ var MAX_GAIA_LOADING_TIME_SEC = 60;
 
   // Frame loading errors.
   /** @const */ var NET_ERROR = {
     ABORTED_BY_USER: 3
   };
 
   /**
@@ skipping 466 matching lines @@
     // Check current network state if currentScreen is a Gaia signin.
     var currentScreen = Oobe.getInstance().currentScreen;
     if (currentScreen.id == SCREEN_GAIA_SIGNIN)
       chrome.send('showGaiaFrameError', [error]);
   };
 
   return {
     GaiaSigninScreen: GaiaSigninScreen
   };
 });