Update {virtual,override,final} to follow C++11 style in chrome/browser/chromeos/drive.

chrome/browser/chromeos/drive/fileapi/webkit_file_stream_writer_impl.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_DRIVE_FILEAPI_WEBKIT_FILE_STREAM_WRITER_IMPL_H_
 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILEAPI_WEBKIT_FILE_STREAM_WRITER_IMPL_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/files/file.h"
@@ skipping 26 matching lines @@
   typedef base::Callback<FileSystemInterface*()> FileSystemGetter;
 
   // Creates a writer for a file at |file_path| on FileSystem returned by
   // |file_system_getter| that starts writing from |offset|.
   // When invalid parameters are set, the first call to Write() method fails.
   // Uses |file_task_runner| for local file operations.
   WebkitFileStreamWriterImpl(const FileSystemGetter& file_system_getter,
                              base::TaskRunner* file_task_runner,
                              const base::FilePath& file_path,
                              int64 offset);
-  virtual ~WebkitFileStreamWriterImpl();
+  ~WebkitFileStreamWriterImpl() override;
 
   // FileWriter override.
-  virtual int Write(net::IOBuffer* buf, int buf_len,
-                    const net::CompletionCallback& callback) override;
-  virtual int Cancel(const net::CompletionCallback& callback) override;
-  virtual int Flush(const net::CompletionCallback& callback) override;
+  int Write(net::IOBuffer* buf,
+            int buf_len,
+            const net::CompletionCallback& callback) override;
+  int Cancel(const net::CompletionCallback& callback) override;
+  int Flush(const net::CompletionCallback& callback) override;
 
  private:
   // Part of Write(). Called after CreateWritableSnapshotFile is completed.
   void WriteAfterCreateWritableSnapshotFile(
       net::IOBuffer* buf,
       int buf_len,
       base::File::Error open_result,
       const base::FilePath& local_path,
       const base::Closure& close_callback_on_ui_thread);
 
@@ skipping 11 matching lines @@
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<WebkitFileStreamWriterImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebkitFileStreamWriterImpl);
 };
 
 }  // namespace internal
 }  // namespace drive
 
 #endif  // CHROME_BROWSER_CHROMEOS_DRIVE_FILEAPI_WEBKIT_FILE_STREAM_WRITER_IMPL_H_