Make SimpleEntryImpl ref counted.

net/disk_cache/simple/simple_backend_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 NET_DISK_CACHE_SIMPLE_SIMPLE_BACKEND_IMPL_H_
 #define NET_DISK_CACHE_SIMPLE_SIMPLE_BACKEND_IMPL_H_
 
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
+#include "base/memory/ref_counted.h"
 #include "base/task_runner.h"
 #include "net/base/cache_type.h"
 #include "net/disk_cache/disk_cache.h"
 
 namespace base {
 class MessageLoopProxy;
 }
 
 namespace disk_cache {
 
@@ skipping 48 matching lines @@
   void InitializeIndex(const CompletionCallback& callback, int result);
 
   // Try to create the directory if it doesn't exist.
   // Must run on Cache Thread.
   static void CreateDirectory(
       base::MessageLoopProxy* io_thread,
       const base::FilePath& path,
       const InitializeIndexCallback& initialize_index_callback);
 
   const base::FilePath path_;
-  scoped_ptr<SimpleIndex> index_;
+  scoped_refptr<SimpleIndex> index_;
   const scoped_refptr<base::TaskRunner> cache_thread_;
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_SIMPLE_SIMPLE_BACKEND_IMPL_H_