Remove ash tray utility functions that are no-ops in MD.

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>
 
@@ skipping 21 matching lines @@
 
   tray::NetworkDetailedView* detailed() { return detailed_; }
 
   // SystemTrayItem
   views::View* CreateTrayView(LoginStatus status) override;
   views::View* CreateDefaultView(LoginStatus status) override;
   views::View* CreateDetailedView(LoginStatus status) override;
   void DestroyTrayView() override;
   void DestroyDefaultView() override;
   void DestroyDetailedView() override;
-  void UpdateAfterLoginStatusChange(LoginStatus status) override;
-  void UpdateAfterShelfAlignmentChange(ShelfAlignment alignment) override;
 
   // NetworkObserver
   void RequestToggleWifi() override;
 
   // NetworkPortalDetectorObserver
   void OnCaptivePortalDetected(const std::string& guid) override;
 
   // TrayNetworkStateObserver::Delegate
   void NetworkStateChanged() override;
 
  private:
   tray::NetworkTrayView* tray_;
   tray::NetworkDefaultView* default_;
   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_