Revert "Start the migration of passwords from the Keychain."

components/password_manager/core/browser/keychain_migration_status_mac.h

Index: components/password_manager/core/browser/keychain_migration_status_mac.h
diff --git a/components/password_manager/core/browser/keychain_migration_status_mac.h b/components/password_manager/core/browser/keychain_migration_status_mac.h
deleted file mode 100644
index 23c2b18e2f67720f81aeb272e82ab3e8f5414c5c..0000000000000000000000000000000000000000
--- a/components/password_manager/core/browser/keychain_migration_status_mac.h
+++ /dev/null
@@ -1,31 +0,0 @@
-// 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 COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_KEYCHAIN_MIGRATION_STATUS_MAC_H
-#define COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_KEYCHAIN_MIGRATION_STATUS_MAC_H
-
-namespace password_manager {
-
-// Status of password migration from the Keychain.
-// The enum is used to back a histogram, and should therefore be treated as
-// append-only.
-enum class MigrationStatus {
-  // Migration wasn't tried yet.
-  NOT_STARTED = 0,
-
-  // Migration finished successfully.
-  MIGRATED,
-
-  // Migration failed once. It should be tried again.
-  FAILED_ONCE,
-
-  // Migration failed twice. It should not be tried again.
-  FAILED_TWICE,
-
-  MIGRATION_STATUS_COUNT,
-};
-
-}  // namespace password_manager
-
-#endif  // COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_KEYCHAIN_MIGRATION_STATUS_MAC_H