servers/quic/quic.go
func (s *Server) QuicHeadersHandler(h http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		s.SetQuicHeaders(w.Header())
		h.ServeHTTP(w, r)
	})
}
func (s *Server) QuicHeadersHandler(h http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		s.SetQuicHeaders(w.Header())
		h.ServeHTTP(w, r)
	})
}
// QuicHeadersHandler should be used as a middleware to set
// quic related headers to TCP server that suggest alternative svc.