ash: Fix system tray avatar not updated regression

chrome/browser/ui/ash/system_tray_delegate_chromeos.h

 // Copyright 2013 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 CHROME_BROWSER_UI_ASH_SYSTEM_TRAY_DELEGATE_CHROMEOS_H_
 #define CHROME_BROWSER_UI_ASH_SYSTEM_TRAY_DELEGATE_CHROMEOS_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 77 matching lines @@
   int GetSystemTrayMenuWidth() override;
   void ActiveUserWasChanged() override;
   bool IsSearchKeyMappedToCapsLock() override;
   void AddCustodianInfoTrayObserver(
       ash::CustodianInfoTrayObserver* observer) override;
   void RemoveCustodianInfoTrayObserver(
       ash::CustodianInfoTrayObserver* observer) override;
   std::unique_ptr<ash::SystemTrayItem> CreateRotationLockTrayItem(
       ash::SystemTray* tray) override;
 
-  // Overridden from user_manager::UserManager::Observer:
-  void OnUserImageChanged(const user_manager::User& user) override;
-
   // Overridden from user_manager::UserManager::UserSessionStateObserver:
-  void UserAddedToSession(const user_manager::User* active_user) override;
-  void ActiveUserChanged(const user_manager::User* active_user) override;
-
   void UserChangedChildStatus(user_manager::User* user) override;
 
  private:
   ash::SystemTrayNotifier* GetSystemTrayNotifier();
 
   void SetProfile(Profile* profile);
 
   bool UnsetProfile(Profile* profile);
 
   void UpdateShowLogoutButtonInTray();
@@ skipping 87 matching lines @@
       custodian_info_changed_observers_;
 
   DISALLOW_COPY_AND_ASSIGN(SystemTrayDelegateChromeOS);
 };
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate();
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_ASH_SYSTEM_TRAY_DELEGATE_CHROMEOS_H_