Improve memory estimate of SpdySessionPool in net/ MemoryDumpProvider.

net/spdy/hpack/hpack_decoder2.h

 // Copyright 2016 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_HPACK_HPACK_DECODER2_H_
 #define NET_SPDY_HPACK_HPACK_DECODER2_H_
 
 // HpackDecoder2
 
 // An HpackDecoder decodes header sets as outlined in
@@ skipping 38 matching lines @@
       SpdyHeadersHandlerInterface* handler) override;
   bool HandleControlFrameHeadersData(const char* headers_data,
                                      size_t headers_data_length) override;
   bool HandleControlFrameHeadersComplete(size_t* compressed_len) override;
   const SpdyHeaderBlock& decoded_block() const override;
   void SetHeaderTableDebugVisitor(
       std::unique_ptr<HpackHeaderTable::DebugVisitorInterface> visitor)
       override;
   void set_max_decode_buffer_size_bytes(
       size_t max_decode_buffer_size_bytes) override;
+  size_t EstimateMemoryUsage() const override;
 
  protected:
   // Override the HpackEntryDecoderListener methods:
 
   void OnIndexedHeader(size_t index) override;
   void OnStartLiteralHeader(HpackEntryType entry_type,
                             size_t maybe_name_index) override;
   void OnNameStart(bool huffman_encoded, size_t len) override;
   void OnNameData(const char* data, size_t len) override;
   void OnNameEnd() override;
@@ skipping 68 matching lines @@
   // is not being provided by the caller.
   // TODO(jamessynge): Consider collapsing several of these bools into a single
   // enum representing the state of the decoding process.
   bool header_block_started_;
 
   DISALLOW_COPY_AND_ASSIGN(HpackDecoder2);
 };
 
 }  // namespace net
 #endif  // NET_SPDY_HPACK_HPACK_DECODER2_H_