Improve memory estimate of SpdySessionPool in net/ MemoryDumpProvider.

net/spdy/hpack/hpack_entry.cc

Index: net/spdy/hpack/hpack_entry.cc
diff --git a/net/spdy/hpack/hpack_entry.cc b/net/spdy/hpack/hpack_entry.cc
index 9a4707915e128c92804e326fea201e08f84e54f7..c6c60f73145268a2f27b3d06f4f40a68de6a77c9 100644
--- a/net/spdy/hpack/hpack_entry.cc
+++ b/net/spdy/hpack/hpack_entry.cc
@@ -6,6 +6,7 @@
 
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/trace_event/memory_usage_estimator.h"
 
 namespace net {
 
@@ -76,4 +77,9 @@ std::string HpackEntry::GetDebugString() const {
          " }";
 }
 
+size_t HpackEntry::EstimateMemoryUsage() const {
+  return base::trace_event::EstimateMemoryUsage(name_) +
+         base::trace_event::EstimateMemoryUsage(value_);
+}
+
 }  // namespace net