Remove Thread wrapper class in forwarder2.

tools/android/forwarder2/thread.h

-// 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.
-
-#ifndef TOOLS_ANDROID_FORWARDER2_THREAD_H_
-#define TOOLS_ANDROID_FORWARDER2_THREAD_H_
-
-#include <pthread.h>
-
-namespace forwarder2 {
-
-// Helper abstract class to create a new thread and curry the
-// call to the Run() method in an object from the new thread.
-class Thread {
- public:
-  Thread();
-  virtual ~Thread();
-
-  // Start thread calling Run().
-  void Start();
-  void Detach();
-  virtual void Join();
-
- protected:
-  virtual void Run() = 0;
-
- private:
-  static void* ThreadCallback(void* arg);
-
-  pthread_t thread_;
-};
-
-}  // namespace forwarder
-
-#endif  // TOOLS_ANDROID_FORWARDER2_THREAD_H_