remoting: Cleanup class/struct fwd declarations

remoting/host/host_power_save_blocker.h

 // Copyright 2016 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 REMOTING_HOST_HOST_POWER_SAVER_BLOCKER_H_
 #define REMOTING_HOST_HOST_POWER_SAVER_BLOCKER_H_
 
 #include <memory>
 #include <string>
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "device/power_save_blocker/power_save_blocker.h"
 #include "remoting/host/host_status_observer.h"
 
 namespace base {
 
 class SingleThreadTaskRunner;
 
 }  // namespace base
 
 namespace remoting {
 
-class AutoThreadTaskRunner;
 class HostStatusMonitor;
 
 // A HostStatusObserver to block screen saver from taking effect during the
 // lifetime of a remoting connection.
 class HostPowerSaveBlocker : public HostStatusObserver {
  public:
   HostPowerSaveBlocker(
       base::WeakPtr<HostStatusMonitor> monitor,
       const scoped_refptr<base::SingleThreadTaskRunner>& ui_task_runner,
       const scoped_refptr<base::SingleThreadTaskRunner>& file_task_runner);
 
   ~HostPowerSaveBlocker() override;
 
   void OnClientConnected(const std::string& jid) override;
   void OnClientDisconnected(const std::string& jid) override;
 
  private:
   friend class HostPowerSaveBlockerTest;
 
   base::WeakPtr<HostStatusMonitor> monitor_;
   scoped_refptr<base::SequencedTaskRunner> ui_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
   std::unique_ptr<device::PowerSaveBlocker> blocker_;
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_HOST_HOST_POWER_SAVER_BLOCKER_H_