Use a direct include of strings headers in chrome/browser/chromeos/.

chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos_unittest.cc

 // 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.
 
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/testing_pref_service.h"
 #include "base/run_loop.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_token_forwarder.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/policy/cloud/cloud_policy_constants.h"
 #include "chrome/browser/policy/cloud/cloud_policy_service.h"
 #include "chrome/browser/policy/cloud/mock_cloud_policy_store.h"
 #include "chrome/browser/policy/cloud/mock_device_management_service.h"
 #include "chrome/browser/policy/cloud/resource_cache.h"
 #include "chrome/browser/policy/mock_configuration_policy_provider.h"
 #include "chrome/browser/policy/proto/cloud/device_management_backend.pb.h"
@@ skipping 480 matching lines @@
 
   // The refresh scheduler takes care of the initial fetch for unmanaged users.
   // It posts a delayed task with 0ms delay in this case, so spinning the loop
   // issues the initial fetch.
   base::RunLoop loop;
   FetchPolicy(
       base::Bind(&base::RunLoop::RunUntilIdle, base::Unretained(&loop)));
 }
 
 }  // namespace policy