Improve memory estimate of SpdySessionPool in net/ MemoryDumpProvider.

net/spdy/hpack/hpack_decoder.h

 // Copyright 2014 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_DECODER_H_
 #define NET_SPDY_HPACK_HPACK_DECODER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 60 matching lines @@
   // a SpdyHeadersHandlerInterface.
   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;
+
  private:
   // Adds the header representation to |decoded_block_|, applying the
   // following rules:
   //  - Multiple values of the Cookie header are joined, delmited by '; '.
   //    This reconstruction is required to properly handle Cookie crumbling
   //    (as per section 8.1.2.5 in RFC 7540).
   //  - Multiple values of other headers are joined and delimited by '\0'.
   //    Note that this may be too accomodating, as the sender's HTTP2 layer
   //    should have already joined and delimited these values.
   //
@@ skipping 54 matching lines @@
 
   // Saved value of --gfe2_reloadable_flag_add_hpack_incremental_decode.
   bool incremental_decode_;
 
   DISALLOW_COPY_AND_ASSIGN(HpackDecoder);
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_HPACK_HPACK_DECODER_H_