add a tracer function to trace sending of Version Negotiation packets

qlog/qlog.go

@@ -50,6 +50,8 @@ func init() {
 const eventChanSize = 50
 
 type tracer struct {
+	logging.NullTracer
+
 	getLogWriter func(p logging.Perspective, connectionID []byte) io.WriteCloser
 }
 
@@ -67,10 +69,6 @@ func (t *tracer) TracerForConnection(_ context.Context, p logging.Perspective, o
 	return nil
 }
 
-func (t *tracer) SentPacket(net.Addr, *logging.Header, protocol.ByteCount, []logging.Frame) {}
-func (t *tracer) DroppedPacket(net.Addr, logging.PacketType, protocol.ByteCount, logging.PacketDropReason) {
-}
-
 type connectionTracer struct {
 	mutex sync.Mutex