Improve memory estimate of SpdySessionPool in net/ MemoryDumpProvider.

net/spdy/spdy_header_block.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_SPDY_SPDY_HEADER_BLOCK_H_
 #define NET_SPDY_SPDY_HEADER_BLOCK_H_
 
 #include <stddef.h>
 
 #include <list>
@@ skipping 200 matching lines @@
                SpdyHeaderBlock::MapType::iterator lookup_result,
                const base::StringPiece key);
 
     SpdyHeaderBlock::MapType* block_;
     SpdyHeaderBlock::Storage* storage_;
     SpdyHeaderBlock::MapType::iterator lookup_result_;
     base::StringPiece key_;
     bool valid_;
   };
 
+  // Returns the estimate of dynamically allocated memory in bytes.
+  size_t EstimateMemoryUsage() const;
+
  private:
   friend class test::SpdyHeaderBlockPeer;
 
   void AppendHeader(const base::StringPiece key, const base::StringPiece value);
   Storage* GetStorage();
   size_t bytes_allocated() const;
 
   // StringPieces held by |block_| point to memory owned by |*storage_|.
   // |storage_| might be nullptr as long as |block_| is empty.
   MapType block_;
@@ skipping 15 matching lines @@
 // to |headers|.  |event_param| must have been created by
 // SpdyHeaderBlockNetLogCallback.  On failure, returns false and clears
 // |headers|.
 NET_EXPORT bool SpdyHeaderBlockFromNetLogParam(
     const base::Value* event_param,
     SpdyHeaderBlock* headers);
 
 }  // namespace net
 
 #endif  // NET_SPDY_SPDY_HEADER_BLOCK_H_