Add a size estimation mechanism to StoragePartitionHttpCacheDataRemover.

net/disk_cache/blockfile/entry_impl_v3.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_BLOCKFILE_ENTRY_IMPL_V3_H_
 #define NET_DISK_CACHE_BLOCKFILE_ENTRY_IMPL_V3_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 65 matching lines @@
 
   const net::BoundNetLog& net_log() const;
 
   // Entry interface.
   void Doom() override;
   void Close() override;
   std::string GetKey() const override;
   base::Time GetLastUsed() const override;
   base::Time GetLastModified() const override;
   int32 GetDataSize(int index) const override;
+  int 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 115 matching lines @@
   // scoped_ptr<SparseControlV3> sparse_;  // Support for sparse entries.
 
   net::BoundNetLog net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(EntryImplV3);
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_BLOCKFILE_ENTRY_IMPL_V3_H_