Add DSR packet count to state and qlog.

Summary: It's useful at the end of a connection to know if we tried DSR.

Reviewed By: jbeshay

Differential Revision: D30545282

fbshipit-source-id: bbb2f3408f7a2d5666676c9e2583bf8fd9f18911

quic/logging/FileQLogger.cpp

@@ -195,6 +195,7 @@ void FileQLogger::addTransportSummary(const TransportSummaryArgs& args) {
       args.currentConnFlowControl,
       args.usedZeroRtt,
       args.quicVersion,
+      args.dsrPacketCount,
       refTime));
 }