cros: Mount the existing eCryptfs vault to start migration.

chrome/browser/ui/webui/chromeos/login/encryption_migration_screen_handler.h

 // Copyright 2017 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_WEBUI_CHROMEOS_LOGIN_ENCRYPTION_MIGRATION_SCREEN_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_ENCRYPTION_MIGRATION_SCREEN_HANDLER_H_
 
 #include "base/macros.h"
 #include "chrome/browser/chromeos/login/screens/encryption_migration_screen_view.h"
 #include "chrome/browser/ui/webui/chromeos/login/base_screen_handler.h"
+#include "chromeos/cryptohome/cryptohome_parameters.h"
 #include "chromeos/dbus/power_manager_client.h"
 #include "chromeos/login/auth/user_context.h"
 #include "third_party/cros_system_api/dbus/cryptohome/dbus-constants.h"
 
 namespace chromeos {
 
 // WebUI implementation of EncryptionMigrationScreenView
 class EncryptionMigrationScreenHandler : public EncryptionMigrationScreenView,
                                          public BaseScreenHandler,
                                          public PowerManagerClient::Observer {
@@ skipping 33 matching lines @@
   void PowerChanged(const power_manager::PowerSupplyProperties& proto) override;
 
   // Handlers for JS API callbacks.
   void HandleStartMigration();
   void HandleSkipMigration();
   void HandleRequestRestart();
 
   // Updates UI state.
   void UpdateUIState(UIState state);
 
-  // Requests cryptohome to start encryption migration.
   void CheckAvailableStorage();
   void OnGetAvailableStorage(int64_t size);
   void WaitBatteryAndMigrate();
   void StartMigration();
+  void OnMountExistingVault(bool success,
+                            cryptohome::MountError return_code,
+                            const std::string& mount_hash);
+  // Creates authorization key for MountEx method using |user_context_|.
+  cryptohome::KeyDefinition GetAuthKey();
 
   // Handlers for cryptohome API callbacks.
   void OnMigrationProgress(cryptohome::DircryptoMigrationStatus status,
                            uint64_t current,
                            uint64_t total);
   void OnMigrationRequested(bool success);
 
   Delegate* delegate_ = nullptr;
   bool show_on_init_ = false;
 
@@ skipping 18 matching lines @@
   bool should_migrate_on_enough_battery_ = false;
 
   base::WeakPtrFactory<EncryptionMigrationScreenHandler> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(EncryptionMigrationScreenHandler);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_ENCRYPTION_MIGRATION_SCREEN_HANDLER_H_