ash: Cleanup class/struct forward declarations

ash/common/system/chromeos/network/tray_network.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 ASH_COMMON_SYSTEM_CHROMEOS_NETWORK_TRAY_NETWORK_H_
 #define ASH_COMMON_SYSTEM_CHROMEOS_NETWORK_TRAY_NETWORK_H_
 
 #include <memory>
 #include <set>
 
 #include "ash/common/system/chromeos/network/network_observer.h"
 #include "ash/common/system/chromeos/network/network_portal_detector_observer.h"
 #include "ash/common/system/chromeos/network/tray_network_state_observer.h"
 #include "ash/common/system/tray/system_tray_item.h"
 #include "base/macros.h"
 #include "base/time/time.h"
 
-namespace chromeos {
-class NetworkState;
-}
-
 namespace ash {
 namespace tray {
 class NetworkDefaultView;
 class NetworkDetailedView;
 class NetworkTrayView;
 }
 
 class TrayNetwork : public SystemTrayItem,
                     public NetworkObserver,
                     public NetworkPortalDetectorObserver,
@@ skipping 29 matching lines @@
   tray::NetworkDetailedView* detailed_;
   bool request_wifi_view_;
   std::unique_ptr<TrayNetworkStateObserver> network_state_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(TrayNetwork);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_CHROMEOS_NETWORK_TRAY_NETWORK_H_