Start the migration of passwords from the Keychain.

components/password_manager/core/common/password_manager_pref_names.cc

 // 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.
 
 #include "components/password_manager/core/common/password_manager_pref_names.h"
 
 namespace password_manager {
 namespace prefs {
 
 const char kAllowToCollectURLBubbleWasShown[] =
     "password_manager_url_collection_bubble.appearance_flag";
 const char kAllowToCollectURLBubbleActivePeriodStartFactor[] =
     "password_manager_url_collection_bubble.active_period_start_id";
 
 #if !defined(OS_MACOSX) && !defined(OS_CHROMEOS) && defined(OS_POSIX)
 const char kLocalProfileId[] = "profile.local_profile_id";
 #endif
 
 #if defined(OS_WIN)
 const char kOsPasswordBlank[] = "password_manager.os_password_blank";
 const char kOsPasswordLastChanged[] =
     "password_manager.os_password_last_changed";
 #endif
 
+#if defined(OS_MACOSX)
+const char kKeychainMigrationStatus[] = "password_manager.keychain_migration";
+#endif
+
 const char kPasswordManagerAllowShowPasswords[] =
     "profile.password_manager_allow_show_passwords";
 const char kPasswordManagerAutoSignin[] =
     "profile.password_manager_auto_signin";
 const char kPasswordManagerSavingEnabled[] = "profile.password_manager_enabled";
 const char kPasswordManagerGroupsForDomains[] =
     "profile.password_manager_groups_for_domains";
 
 }  // namespace prefs
 }  // namespace password_manager