Move WriteFile and WriteFileDescriptor from file_util to base namespace.

chrome/browser/media_galleries/mac/mtp_device_delegate_impl_mac_unittest.mm

 // 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.
 
 #import <Foundation/Foundation.h>
 #import <ImageCaptureCore/ImageCaptureCore.h>
 
 #include "base/file_util.h"
 #include "base/files/file.h"
 #include "base/files/scoped_temp_dir.h"
@@ skipping 84 matching lines @@
                 contextInfo:(void*)contextInfo {
   base::FilePath saveDir(base::SysNSStringToUTF8(
       [[options objectForKey:ICDownloadsDirectoryURL] path]));
   std::string saveAsFilename =
       base::SysNSStringToUTF8([options objectForKey:ICSaveAsFilename]);
   // It appears that the ImageCapture library adds an extension to the requested
   // filename. Do that here to require a rename.
   saveAsFilename += ".jpg";
   base::FilePath toBeSaved = saveDir.Append(saveAsFilename);
   ASSERT_EQ(static_cast<int>(strlen(kTestFileContents)),
-            file_util::WriteFile(toBeSaved, kTestFileContents,
-                                 strlen(kTestFileContents)));
+            base::WriteFile(toBeSaved, kTestFileContents,
+                            strlen(kTestFileContents)));
 
   NSMutableDictionary* returnOptions =
       [NSMutableDictionary dictionaryWithDictionary:options];
   [returnOptions setObject:base::SysUTF8ToNSString(saveAsFilename)
                     forKey:ICSavedFilename];
 
   [static_cast<NSObject<ICCameraDeviceDownloadDelegate>*>(downloadDelegate)
    didDownloadFile:file
              error:nil
            options:returnOptions
@@ skipping 438 matching lines @@
                          temp_dir_.path().Append("target")));
 
   EXPECT_EQ(base::File::FILE_OK,
             DownloadFile(base::FilePath("/ic:id/filename"),
                          temp_dir_.path().Append("target")));
   std::string contents;
   EXPECT_TRUE(base::ReadFileToString(temp_dir_.path().Append("target"),
                                      &contents));
   EXPECT_EQ(kTestFileContents, contents);
 }