Updating server dependancies (#6712)

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

@@ -2,14 +2,20 @@
 // this source code is governed by a BSD-style license that can be found in the
 // LICENSE file.
 
-// +build !appengine
-
 package websocket
 
-import "unsafe"
+import (
+	"math/rand"
+	"unsafe"
+)
 
 const wordSize = int(unsafe.Sizeof(uintptr(0)))
 
+func newMaskKey() [4]byte {
+	n := rand.Uint32()
+	return [4]byte{byte(n), byte(n >> 8), byte(n >> 16), byte(n >> 24)}
+}
+
 func maskBytes(key [4]byte, pos int, b []byte) int {
 
 	// Mask one byte at a time for small buffers.