NewTimeoutTransport some useless code

[holyorevil]

When I was looking at the code,i found that function named NewTimeoutTransport both give value to Transport.Dialcontext and Transport.Dial，and only Transport.Dialcontext is validate, The code is as follows:

func NewTimeoutTransport(info TLSInfo, dialtimeoutd, rdtimeoutd, wtimeoutd time.Duration) (*http.Transport, error) {
	tr, err := NewTransport(info, dialtimeoutd)
	if err != nil {
		return nil, err
	}

	if rdtimeoutd != 0 || wtimeoutd != 0 {
		tr.MaxIdleConnsPerHost = -1
	} else {
		tr.MaxIdleConnsPerHost = 1024
	}
        // here
	tr.Dial = (&rwTimeoutDialer{
		Dialer: net.Dialer{
			Timeout:   dialtimeoutd,
			KeepAlive: 30 * time.Second,
		},
		rdtimeoutd: rdtimeoutd,
		wtimeoutd:  wtimeoutd,
	}).Dial
	return tr, nil
}


func NewTransport(info TLSInfo, dialtimeoutd time.Duration) (*http.Transport, error) {
	cfg, err := info.ClientConfig()
	if err != nil {
		return nil, err
	}

	t := &http.Transport{
		Proxy: http.ProxyFromEnvironment,
                // here
		DialContext: (&net.Dialer{
			Timeout: dialtimeoutd,
			KeepAlive: 30 * time.Second,
		}).DialContext,
		// value taken from http.DefaultTransport
		TLSHandshakeTimeout: 10 * time.Second,
		TLSClientConfig:     cfg,
	}

	dialer := &net.Dialer{
		Timeout:   dialtimeoutd,
		KeepAlive: 30 * time.Second,
	}

	dialContext := func(ctx context.Context, net, addr string) (net.Conn, error) {
		return dialer.DialContext(ctx, "unix", addr)
	}
	tu := &http.Transport{
		Proxy:               http.ProxyFromEnvironment,
		DialContext:         dialContext,
		TLSHandshakeTimeout: 10 * time.Second,
		TLSClientConfig:     cfg,
		IdleConnTimeout: time.Microsecond,
	}
	ut := &unixTransport{tu}

	t.RegisterProtocol("unix", ut)
	t.RegisterProtocol("unixs", ut)

	return t, nil
}