Refactor cache counting into a separate helper class

net/disk_cache/memory/mem_entry_impl.h

 // Copyright (c) 2012 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_MEMORY_MEM_ENTRY_IMPL_H_
 #define NET_DISK_CACHE_MEMORY_MEM_ENTRY_IMPL_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 86 matching lines @@
   // the entry was modified, also update |last_modified_|.
   void UpdateStateOnUse(EntryModified modified_enum);
 
   // From disk_cache::Entry:
   void Doom() override;
   void Close() override;
   std::string GetKey() const override;
   base::Time GetLastUsed() const override;
   base::Time GetLastModified() const override;
   int32_t GetDataSize(int index) const override;
+  int64_t GetEntrySize() const override;
   int ReadData(int index,
                int offset,
                IOBuffer* buf,
                int buf_len,
                const CompletionCallback& callback) override;
   int WriteData(int index,
                 int offset,
                 IOBuffer* buf,
                 int buf_len,
                 const CompletionCallback& callback,
@@ skipping 68 matching lines @@
   bool doomed_;               // True if this entry was removed from the cache.
 
   net::NetLogWithSource net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(MemEntryImpl);
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_MEMORY_MEM_ENTRY_IMPL_H_