iwyu: Include stringprintf.h where appropriate, part 3.

chrome/common/net/gaia/gaia_auth_fetcher_unittest.cc

 // Copyright (c) 2011 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.
 //
 // A complete set of unit tests for GaiaAuthFetcher.
 // Originally ported from GoogleAuthenticator tests.
 
 #include <string>
 
 #include "base/message_loop.h"
-#include "base/string_util.h"
+#include "base/stringprintf.h"
 #include "chrome/common/net/gaia/gaia_auth_consumer.h"
 #include "chrome/common/net/gaia/gaia_auth_fetcher.h"
 #include "chrome/common/net/gaia/gaia_auth_fetcher_unittest.h"
 #include "chrome/common/net/gaia/google_service_auth_error.h"
 #include "chrome/common/net/http_return.h"
 #include "chrome/common/net/test_url_fetcher_factory.h"
 #include "chrome/common/net/url_fetcher.h"
 #include "chrome/test/testing_profile.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/net_errors.h"
@@ skipping 466 matching lines @@
   EXPECT_TRUE(auth.HasPendingFetch());
   auth.OnURLFetchComplete(
       NULL,
       issue_auth_token_source_,
       net::URLRequestStatus(net::URLRequestStatus::SUCCESS, 0),
       RC_FORBIDDEN,
       cookies_,
       "");
   EXPECT_FALSE(auth.HasPendingFetch());
 }