Update vendored dependencies.

vendor/github.com/gorilla/websocket/client.go

@@ -389,32 +389,3 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 	netConn = nil // to avoid close in defer.
 	return conn, resp, nil
 }
-
-// cloneTLSConfig clones all public fields except the fields
-// SessionTicketsDisabled and SessionTicketKey. This avoids copying the
-// sync.Mutex in the sync.Once and makes it safe to call cloneTLSConfig on a
-// config in active use.
-func cloneTLSConfig(cfg *tls.Config) *tls.Config {
-	if cfg == nil {
-		return &tls.Config{}
-	}
-	return &tls.Config{
-		Rand:                     cfg.Rand,
-		Time:                     cfg.Time,
-		Certificates:             cfg.Certificates,
-		NameToCertificate:        cfg.NameToCertificate,
-		GetCertificate:           cfg.GetCertificate,
-		RootCAs:                  cfg.RootCAs,
-		NextProtos:               cfg.NextProtos,
-		ServerName:               cfg.ServerName,
-		ClientAuth:               cfg.ClientAuth,
-		ClientCAs:                cfg.ClientCAs,
-		InsecureSkipVerify:       cfg.InsecureSkipVerify,
-		CipherSuites:             cfg.CipherSuites,
-		PreferServerCipherSuites: cfg.PreferServerCipherSuites,
-		ClientSessionCache:       cfg.ClientSessionCache,
-		MinVersion:               cfg.MinVersion,
-		MaxVersion:               cfg.MaxVersion,
-		CurvePreferences:         cfg.CurvePreferences,
-	}
-}