chromeos: Replace user image notifications with observer

chrome/browser/chromeos/login/users/fake_chrome_user_manager.h

 // Copyright 2015 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_CHROMEOS_LOGIN_USERS_FAKE_CHROME_USER_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_FAKE_CHROME_USER_MANAGER_H_
 
 #include <map>
 #include <memory>
 #include <string>
@@ skipping 77 matching lines @@
   bool IsLoggedInAsUserWithGaiaAccount() const override;
   bool IsLoggedInAsChildUser() const override;
   bool IsLoggedInAsPublicAccount() const override;
   bool IsLoggedInAsGuest() const override;
   bool IsLoggedInAsSupervisedUser() const override;
   bool IsLoggedInAsKioskApp() const override;
   bool IsLoggedInAsArcKioskApp() const override;
   bool IsLoggedInAsStub() const override;
   bool IsUserNonCryptohomeDataEphemeral(
       const AccountId& account_id) const override;
-  void AddObserver(UserManager::Observer* obs) override;
-  void RemoveObserver(UserManager::Observer* obs) override;
-  void AddSessionStateObserver(
-      UserManager::UserSessionStateObserver* obs) override;
-  void RemoveSessionStateObserver(
-      UserManager::UserSessionStateObserver* obs) override;
-  void NotifyLocalStateChanged() override;
   void ChangeUserChildStatus(user_manager::User* user, bool is_child) override;
   bool AreSupervisedUsersAllowed() const override;
   PrefService* GetLocalState() const override;
   bool GetPlatformKnownUserId(const std::string& user_email,
                               const std::string& gaia_id,
                               AccountId* out_account_id) const override;
   const AccountId& GetGuestAccountId() const override;
   bool IsFirstExecAfterBoot() const override;
   void AsyncRemoveCryptohome(const AccountId& account_id) const override;
   bool IsGuestAccountId(const AccountId& account_id) const override;
@@ skipping 94 matching lines @@
   // Specific flows by user e-mail.
   // Keys should be canonicalized before access.
   FlowMap specific_flows_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeChromeUserManager);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_FAKE_CHROME_USER_MANAGER_H_