Improve memory estimate of SpdySessionPool in net/ MemoryDumpProvider.

net/spdy/hpack/hpack_huffman_table.cc

Index: net/spdy/hpack/hpack_huffman_table.cc
diff --git a/net/spdy/hpack/hpack_huffman_table.cc b/net/spdy/hpack/hpack_huffman_table.cc
index 0e3ca1b060eb5f49178ab881724dc6da60bf5b57..2d361db76000853a353aa2471c88214f49dfa0ed 100644
--- a/net/spdy/hpack/hpack_huffman_table.cc
+++ b/net/spdy/hpack/hpack_huffman_table.cc
@@ -12,6 +12,7 @@
 #include "base/numerics/safe_conversions.h"
 #include "net/spdy/hpack/hpack_input_stream.h"
 #include "net/spdy/hpack/hpack_output_stream.h"
+#include "net/spdy/platform/api/spdy_estimate_memory_usage.h"
 
 namespace net {
 
@@ -318,4 +319,11 @@ bool HpackHuffmanTable::GenericDecodeString(HpackInputStream* in,
   return false;
 }
 
+size_t HpackHuffmanTable::EstimateMemoryUsage() const {
+  return SpdyEstimateMemoryUsage(decode_tables_) +
+         SpdyEstimateMemoryUsage(decode_entries_) +
+         SpdyEstimateMemoryUsage(code_by_id_) +
+         SpdyEstimateMemoryUsage(length_by_id_);
+}
+
 }  // namespace net