Revert "Migrate the IndexedDB backend from Blink to Chromium"

content/browser/indexed_db/indexed_db.h

-// Copyright (c) 2013 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 CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_H_
-#define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_H_
-
-namespace content {
-
-namespace indexed_db {
-
-enum TransactionMode {
-  TRANSACTION_READ_ONLY = 0,
-  TRANSACTION_READ_WRITE = 1,
-  TRANSACTION_VERSION_CHANGE = 2
-};
-
-enum CursorDirection {
-  CURSOR_NEXT = 0,
-  CURSOR_NEXT_NO_DUPLICATE = 1,
-  CURSOR_PREV = 2,
-  CURSOR_PREV_NO_DUPLICATE = 3,
-};
-
-enum CursorType {
-  CURSOR_KEY_AND_VALUE = 0,
-  CURSOR_KEY_ONLY
-};
-
-}  // namespace indexed_db
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_H_