Implement a basic UI flow for cryptohome encryption migration.

chromeos/login/auth/login_performer.h

 // Copyright 2014 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 CHROMEOS_LOGIN_AUTH_LOGIN_PERFORMER_H_
 #define CHROMEOS_LOGIN_AUTH_LOGIN_PERFORMER_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 73 matching lines @@
                            bool use_guest_mount);
 
   // Performs a login into the ARC kiosk mode account with |arc_app_account_id|.
   void LoginAsArcKioskAccount(const AccountId& arc_app_account_id);
 
   // AuthStatusConsumer implementation:
   void OnAuthFailure(const AuthFailure& error) override;
   void OnAuthSuccess(const UserContext& user_context) override;
   void OnOffTheRecordAuthSuccess() override;
   void OnPasswordChangeDetected() override;
-  void OnOldEncryptionDetected() override;
+  void OnOldEncryptionDetected(const UserContext& user_context) override;
 
   // Migrates cryptohome using |old_password| specified.
   void RecoverEncryptedData(const std::string& old_password);
 
   // Reinitializes cryptohome with the new password.
   void ResyncEncryptedData();
 
   // Returns latest auth error.
   const GoogleServiceAuthError& error() const {
     return last_login_failure_.error();
@@ skipping 119 matching lines @@
   // Authorization mode type.
   AuthorizationMode auth_mode_;
 
   base::WeakPtrFactory<LoginPerformer> weak_factory_;
   DISALLOW_COPY_AND_ASSIGN(LoginPerformer);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_LOGIN_AUTH_LOGIN_PERFORMER_H_