Remove Hung plugin detector

chrome/common/worker_thread_ticker.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 CHROME_COMMON_WORKER_THREAD_TICKER_H_
-#define CHROME_COMMON_WORKER_THREAD_TICKER_H_
-
-#include <vector>
-
-#include "base/macros.h"
-#include "base/synchronization/lock.h"
-#include "base/threading/thread.h"
-
-// This class provides the following functionality:
-// It invokes a set of registered handlers at periodic intervals in
-// the context of an arbitrary worker thread.
-// The timer runs on a separate thread, so it will run even if the current
-// thread is hung. Similarly, the callbacks will be called on a separate
-// thread so they won't block the main thread.
-class WorkerThreadTicker {
- public:
-  // This callback interface to be implemented by clients of this
-  // class
-  class Callback {
-   public:
-    // Gets invoked when the timer period is up
-    virtual void OnTick() = 0;
-
-   protected:
-    virtual ~Callback() {}
-  };
-
-  // tick_interval is the periodic interval in which to invoke the
-  // registered handlers (in milliseconds)
-  explicit WorkerThreadTicker(int tick_interval);
-
-  ~WorkerThreadTicker();
-
-  // Registers a callback handler interface
-  // tick_handler is the handler interface to register. The ownership of this
-  // object is not transferred to this class.
-  bool RegisterTickHandler(Callback *tick_handler);
-
-  // Unregisters a callback handler interface
-  // tick_handler is the handler interface to unregister
-  bool UnregisterTickHandler(Callback *tick_handler);
-
-  // Starts the ticker. Returns false if the ticker is already running
-  // or if the Start fails.
-  bool Start();
-  // Stops the ticker and waits for all callbacks. to be done. This method
-  // does not provide a way to stop without waiting for the callbacks to be
-  // done because this is inherently risky.
-  // Returns false is the ticker is not running
-  bool Stop();
-  bool IsRunning() const {
-    return is_running_;
-  }
-
-  void set_tick_interval(int tick_interval) {
-    tick_interval_ = base::TimeDelta::FromMilliseconds(tick_interval);
-  }
-
- private:
-  void ScheduleTimerTask();
-
-  void TimerTask();
-
-  // A list type that holds all registered callback interfaces
-  typedef std::vector<Callback*> TickHandlerListType;
-
-  // Lock to protect is_running_ and tick_handler_list_
-  base::Lock lock_;
-
-  base::Thread timer_thread_;
-  bool is_running_;
-
-  // The interval at which the callbacks are to be invoked
-  base::TimeDelta tick_interval_;
-
-  // A list that holds all registered callback interfaces
-  TickHandlerListType tick_handler_list_;
-
-  DISALLOW_COPY_AND_ASSIGN(WorkerThreadTicker);
-};
-
-#endif  // CHROME_COMMON_WORKER_THREAD_TICKER_H_