Add IndexedDBValue wrapper class to group blob info with bits.

content/browser/indexed_db/indexed_db_cursor.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_CURSOR_H_
 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_CURSOR_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 18 matching lines @@
   void Advance(uint32 count, scoped_refptr<IndexedDBCallbacks> callbacks);
   void Continue(scoped_ptr<IndexedDBKey> key,
                 scoped_ptr<IndexedDBKey> primary_key,
                 scoped_refptr<IndexedDBCallbacks> callbacks);
   void PrefetchContinue(int number_to_fetch,
                         scoped_refptr<IndexedDBCallbacks> callbacks);
   void PrefetchReset(int used_prefetches, int unused_prefetches);
 
   const IndexedDBKey& key() const { return cursor_->key(); }
   const IndexedDBKey& primary_key() const { return cursor_->primary_key(); }
-  std::string* Value() const {
+  IndexedDBValue* Value() const {
     return (cursor_type_ == indexed_db::CURSOR_KEY_ONLY) ? NULL
                                                          : cursor_->value();
   }
   void Close();
 
   void CursorIterationOperation(scoped_ptr<IndexedDBKey> key,
                                 scoped_ptr<IndexedDBKey> primary_key,
                                 scoped_refptr<IndexedDBCallbacks> callbacks,
                                 IndexedDBTransaction* transaction);
   void CursorAdvanceOperation(uint32 count,
@@ skipping 17 matching lines @@
   scoped_ptr<IndexedDBBackingStore::Cursor> cursor_;
   // Must be destroyed before transaction_.
   scoped_ptr<IndexedDBBackingStore::Cursor> saved_cursor_;
 
   bool closed_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_CURSOR_H_