IndexedDB: Eliminate WebIDBCursor wrapper

content/browser/indexed_db/webidbcursor_impl.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_WEBIDBCURSOR_IMPL_H_
-#define CONTENT_BROWSER_INDEXED_DB_WEBIDBCURSOR_IMPL_H_
-
-#include "base/memory/ref_counted.h"
-
-namespace content {
-class IndexedDBCursor;
-class IndexedDBCallbacksBase;
-class IndexedDBKey;
-
-class WebIDBCursorImpl {
- public:
-  explicit WebIDBCursorImpl(scoped_refptr<IndexedDBCursor> cursor);
-  virtual ~WebIDBCursorImpl();
-
-  virtual void advance(unsigned long, IndexedDBCallbacksBase* callbacks);
-  virtual void continueFunction(const IndexedDBKey& key,
-                                IndexedDBCallbacksBase* callbacks);
-  virtual void prefetchContinue(int number_to_fetch,
-                                IndexedDBCallbacksBase* callbacks);
-  virtual void prefetchReset(int used_prefetches, int unused_prefetches);
-
- private:
-  scoped_refptr<IndexedDBCursor> idb_cursor_backend_;
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_INDEXED_DB_WEBIDBCURSOR_IMPL_H_