http: there is no corked property of stream

Do not check/use unexistent property, use `OutgoingMessage` instead.

PR-URL: #18325
Reviewed-By: Mithun Sasidharan <mithunsasidharan89@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: indutny

lib/_http_outgoing.js

@@ -38,6 +38,8 @@ const errors = require('internal/errors');
 const { CRLF, debug } = common;
 const { utcDate } = internalHttp;
 
+const kIsCorked = Symbol('isCorked');
+
 var RE_FIELDS =
   /^(?:Connection|Transfer-Encoding|Content-Length|Date|Expect|Trailer|Upgrade)$/i;
 var RE_CONN_VALUES = /(?:^|\W)close|upgrade(?:$|\W)/ig;
@@ -99,6 +101,7 @@ function OutgoingMessage() {
 
   this.finished = false;
   this._headerSent = false;
+  this[kIsCorked] = false;
 
   this.socket = null;
   this.connection = null;
@@ -657,9 +660,10 @@ function write_(msg, chunk, encoding, callback, fromEnd) {
   // signal the user to keep writing.
   if (chunk.length === 0) return true;
 
-  if (!fromEnd && msg.connection && !msg.connection.corked) {
+  if (!fromEnd && msg.connection && !msg[kIsCorked]) {
     msg.connection.cork();
-    process.nextTick(connectionCorkNT, msg.connection);
+    msg[kIsCorked] = true;
+    process.nextTick(connectionCorkNT, msg, msg.connection);
   }
 
   var len, ret;
@@ -688,7 +692,8 @@ function writeAfterEndNT(err, callback) {
 }
 
 
-function connectionCorkNT(conn) {
+function connectionCorkNT(msg, conn) {
+  msg[kIsCorked] = false;
   conn.uncork();
 }