Cleanup: Remove unneeded forward declarations from remoting.

remoting/host/host_status_observer.h

 // Copyright (c) 2011 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_STATUS_OBSERVER_H_
-#define REMOTING_HOST_STATUS_OBSERVER_H_
+#ifndef REMOTING_HOST_HOST_STATUS_OBSERVER_H_
+#define REMOTING_HOST_HOST_STATUS_OBSERVER_H_
 
 #include <string>
 
 namespace remoting {
 class SignalStrategy;
 
-namespace protocol {
-class ConnectionToClient;
-}
-
 // Interface for host status observer. All methods are invoked on the
 // network thread.
 class HostStatusObserver {
  public:
   HostStatusObserver() { }
   virtual ~HostStatusObserver() { }
 
   // Called when status of the signalling channel changes.
   virtual void OnSignallingConnected(SignalStrategy* signal_strategy,
                                      const std::string& full_jid) = 0;
   virtual void OnSignallingDisconnected() = 0;
 
   // Called when an unauthorized user attempts to connect to the host.
   virtual void OnAccessDenied() = 0;
 
   // Called when a client authenticates, or disconnects. Observers
   // must not tear-down ChromotingHost state on receipt of this
   // callback; it is purely informational.
   virtual void OnClientAuthenticated(const std::string& jid) = 0;
   virtual void OnClientDisconnected(const std::string& jid) = 0;
 
   // Called when the host shuts down.
   virtual void OnShutdown() = 0;
 };
 
 }  // namespace remoting
 
-#endif  // REMOTING_HOST_STATUS_OBSERVER_H_
+#endif  // REMOTING_HOST_HOST_STATUS_OBSERVER_H_