Delete unused base/worker.{cc,h}.

webrtc/base/worker.h

-/*
- *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-#ifndef WEBRTC_BASE_WORKER_H_
-#define WEBRTC_BASE_WORKER_H_
-
-#include "webrtc/base/constructormagic.h"
-#include "webrtc/base/messagehandler.h"
-
-namespace rtc {
-
-class Thread;
-
-// A worker is an object that performs some specific long-lived task in an
-// event-driven manner.
-// The only method that should be considered thread-safe is HaveWork(), which
-// allows you to signal the availability of work from any thread. All other
-// methods are thread-hostile. Specifically:
-// StartWork()/StopWork() should not be called concurrently with themselves or
-// each other, and it is an error to call them while the worker is running on
-// a different thread.
-// The destructor may not be called if the worker is currently running
-// (regardless of the thread), but you can call StopWork() in a subclass's
-// destructor.
-class Worker : private MessageHandler {
- public:
-  Worker();
-
-  // Destroys this Worker, but it must have already been stopped via StopWork().
-  ~Worker() override;
-
-  // Attaches the worker to the current thread and begins processing work if not
-  // already doing so.
-  bool StartWork();
-  // Stops processing work if currently doing so and detaches from the current
-  // thread.
-  bool StopWork();
-
- protected:
-  // Signal that work is available to be done. May only be called within the
-  // lifetime of a OnStart()/OnStop() pair.
-  void HaveWork();
-
-  // These must be implemented by a subclass.
-  // Called on the worker thread to start working.
-  virtual void OnStart() = 0;
-  // Called on the worker thread when work has been signalled via HaveWork().
-  virtual void OnHaveWork() = 0;
-  // Called on the worker thread to stop working. Upon return, any pending
-  // OnHaveWork() calls are cancelled.
-  virtual void OnStop() = 0;
-
- private:
-  // Inherited from MessageHandler.
-  void OnMessage(Message* msg) override;
-
-  // The thread that is currently doing the work.
-  Thread *worker_thread_;
-
-  RTC_DISALLOW_COPY_AND_ASSIGN(Worker);
-};
-
-}  // namespace rtc
-
-#endif  // WEBRTC_BASE_WORKER_H_