Attempt four at landing the "histogram.h removed from message_loop.h" patch.

chrome/common/net/gaia/gaia_authenticator2.h

 // Copyright (c) 2010 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.
 
 #ifndef CHROME_COMMON_NET_GAIA_GAIA_AUTHENTICATOR2_H_
 #define CHROME_COMMON_NET_GAIA_GAIA_AUTHENTICATOR2_H_
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
+#include "base/scoped_ptr.h"
 #include "chrome/common/net/gaia/gaia_auth_consumer.h"
 #include "chrome/common/net/url_fetcher.h"
 #include "googleurl/src/gurl.h"
 
 // Authenticate a user against the Google Accounts ClientLogin API
 // with various capabilities and return results to a GaiaAuthConsumer.
 //
 // In the future, we will also issue auth tokens from this class.
 // This class should be used on a single thread, but it can be whichever thread
 // that you like.
@@ skipping 126 matching lines @@
 
   friend class GaiaAuthenticator2Test;
   FRIEND_TEST_ALL_PREFIXES(GaiaAuthenticator2Test, LoginNetFailure);
   FRIEND_TEST_ALL_PREFIXES(GaiaAuthenticator2Test, CheckNormalErrorCode);
   FRIEND_TEST_ALL_PREFIXES(GaiaAuthenticator2Test, CheckTwoFactorResponse);
 
   DISALLOW_COPY_AND_ASSIGN(GaiaAuthenticator2);
 };
 
 #endif  // CHROME_COMMON_NET_GAIA_GAIA_AUTHENTICATOR2_H_