Use SingleThreadTaskRunner instead of MessageLoopProxy in remoting/host.

remoting/host/policy_hack/nat_policy.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 REMOTING_HOST_POLICY_HACK_NAT_POLICY_H_
 #define REMOTING_HOST_POLICY_HACK_NAT_POLICY_H_
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 
 namespace base {
 class DictionaryValue;
-class MessageLoopProxy;
+class SingleThreadTaskRunner;
 class TimeDelta;
 class WaitableEvent;
 }  // namespace base
 
 namespace remoting {
 namespace policy_hack {
 
 // Watches for changes to the managed remote access host NAT policies.
 // If StartWatching() has been called, then before this object can be deleted,
 // StopWatching() have completed (the provided |done| event must be signaled).
 class NatPolicy {
  public:
   // Called with the current status of whether or not NAT traversal is enabled.
   typedef base::Callback<void(bool)> NatEnabledCallback;
 
-  explicit NatPolicy(base::MessageLoopProxy* message_loop_proxy);
+  explicit NatPolicy(scoped_refptr<base::SingleThreadTaskRunner> task_runner);
   virtual ~NatPolicy();
 
   // This guarantees that the |nat_enabled_cb| is called at least once with
   // the current policy.  After that, |nat_enabled_cb| will be called whenever
   // a change to the nat policy is detected.
   virtual void StartWatching(const NatEnabledCallback& nat_enabled_cb);
 
   // Should be called after StartWatching() before the object is deleted. Calls
   // just wait for |done| to be signaled before deleting the object.
   virtual void StopWatching(base::WaitableEvent* done);
 
   // Implemented by each platform.  This message loop should be an IO message
   // loop.
-  static NatPolicy* Create(base::MessageLoopProxy* message_loop_proxy);
+  static NatPolicy* Create(
+      scoped_refptr<base::SingleThreadTaskRunner> task_runner);
 
  protected:
   virtual void StartWatchingInternal() = 0;
   virtual void StopWatchingInternal() = 0;
   virtual void Reload() = 0;
 
   // Used to check if the class is on the right thread.
   bool OnPolicyThread() const;
 
   // Takes the policy dictionary from the OS specific store and extracts the
   // NAT traversal setting.
   void UpdateNatPolicy(base::DictionaryValue* new_policy);
 
   // Used for time-based reloads in case something goes wrong with the
   // notification system.
   void ScheduleFallbackReloadTask();
   void ScheduleReloadTask(const base::TimeDelta& delay);
 
   static const char kNatPolicyName[];
 
  private:
-  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
   NatEnabledCallback nat_enabled_cb_;
   bool current_nat_enabled_state_;
   bool first_state_published_;
 
   // Allows us to cancel any inflight FileWatcher events or scheduled reloads.
   base::WeakPtrFactory<NatPolicy> weak_factory_;
 };
 
 }  // namespace policy_hack
 }  // namespace remoting
 
 #endif  // REMOTING_HOST_POLICY_HACK_NAT_POLICY_H_