Move WriteFile and WriteFileDescriptor from file_util to base namespace.

chrome/browser/sync_file_system/drive_backend/fake_drive_service_helper.cc

 // Copyright 2014 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/sync_file_system/drive_backend/fake_drive_service_helper.h"
 
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
@@ skipping 326 matching lines @@
   ASSERT_TRUE(base_dir_.CreateUniqueTempDir());
   temp_dir_ = base_dir_.path().Append(FPL("tmp"));
   ASSERT_TRUE(base::CreateDirectory(temp_dir_));
 }
 
 base::FilePath FakeDriveServiceHelper::WriteToTempFile(
     const std::string& content) {
   base::FilePath temp_file;
   EXPECT_TRUE(base::CreateTemporaryFileInDir(temp_dir_, &temp_file));
   EXPECT_EQ(static_cast<int>(content.size()),
-            file_util::WriteFile(temp_file, content.data(), content.size()));
+            base::WriteFile(temp_file, content.data(), content.size()));
   return temp_file;
 }
 
 }  // namespace drive_backend
 }  // namespace sync_file_system