Move ReadFileToString to the base namespace.

cloud_print/service/win/cloud_print_service_config.cc

 // 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.
 
 #include <atlbase.h>
 #include <atlapp.h>  // NOLINT
 
 #include "base/at_exit.h"
 #include "base/bind.h"
 #include "base/callback_helpers.h"
@@ skipping 354 matching lines @@
 
   if (!setup.is_xps_available())
     return ShowError(IDS_ERROR_NO_XPS);
 
   base::FilePath file = setup.user_data_dir();
   file = file.Append(chrome::kServiceStateFileName);
 
   std::string proxy_id;
   std::string contents;
 
-  if (file_util::ReadFileToString(file, &contents)) {
+  if (base::ReadFileToString(file, &contents)) {
     ServiceState service_state;
     if (service_state.FromString(contents))
       proxy_id = service_state.proxy_id();
   }
   PostUITask(base::Bind(&SetupDialog::AskToCloseChrome, this));
   contents = ChromeLauncher::CreateServiceStateFile(proxy_id, setup.printers());
 
   if (contents.empty())
     return ShowError(IDS_ERROR_FAILED_CREATE_CONFIG);
 
@@ skipping 57 matching lines @@
   scoped_refptr<SetupDialog> dialog(new SetupDialog());
   dialog->Create(NULL);
   dialog->ShowWindow(SW_SHOW);
   scoped_ptr<SetupDialog::MessageFilter> filter(
       new SetupDialog::MessageFilter(dialog));
   loop.SetMessageFilter(filter.Pass());
 
   loop.Run();
   return 0;
 }