Improve memory estimate of SpdySessionPool in net/ MemoryDumpProvider.

net/base/host_port_pair.cc

Index: net/base/host_port_pair.cc
diff --git a/net/base/host_port_pair.cc b/net/base/host_port_pair.cc
index 68fb0b650135e885c531b27908ef2cb819d5414c..b40cb7c7af6dc3e1766828d813c1b9d281d41f22 100644
--- a/net/base/host_port_pair.cc
+++ b/net/base/host_port_pair.cc
@@ -49,10 +49,6 @@ HostPortPair HostPortPair::FromString(const std::string& str) {
   return host_port_pair;
 }
 
-size_t HostPortPair::EstimateMemoryUsage(const HostPortPair& pair) {
-  return base::trace_event::EstimateMemoryUsage(pair.host());
-}
-
 std::string HostPortPair::ToString() const {
   std::string ret(HostForURL());
   ret += ':';
@@ -79,4 +75,8 @@ std::string HostPortPair::HostForURL() const {
   return host_;
 }
 
+size_t HostPortPair::EstimateMemoryUsage() const {
+  return base::trace_event::EstimateMemoryUsage(host_);
+}
+
 }  // namespace net