use submodule

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

@@ -1,18 +0,0 @@
-// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build !go1.8
-
-package websocket
-
-func (c *Conn) writeBufs(bufs ...[]byte) error {
-	for _, buf := range bufs {
-		if len(buf) > 0 {
-			if _, err := c.conn.Write(buf); err != nil {
-				return err
-			}
-		}
-	}
-	return nil
-}