http: simplify timeout handling

Avoids allocating and registering extra listeners for 'timeout'.

PR-URL: #29200
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

lib/_http_client.js

@@ -625,6 +625,10 @@ function responseOnEnd() {
   const res = this;
   const req = this.req;
 
+  if (req.socket && req.timeoutCb) {
+    req.socket.removeListener('timeout', emitRequestTimeout);
+  }
+
   req._ended = true;
   if (!req.shouldKeepAlive || req.finished)
     responseKeepAlive(res, req);
@@ -680,11 +684,17 @@ function tickOnSocket(req, socket) {
   req.emit('socket', socket);
 }
 
+function emitRequestTimeout() {
+  const req = this._httpMessage;
+  if (req) {
+    req.emit('timeout');
+  }
+}
+
 function listenSocketTimeout(req) {
   if (req.timeoutCb) {
     return;
   }
-  const emitRequestTimeout = () => req.emit('timeout');
   // Set timeoutCb so it will get cleaned up on request end.
   req.timeoutCb = emitRequestTimeout;
   // Delegate socket timeout event.
@@ -695,12 +705,6 @@ function listenSocketTimeout(req) {
       socket.once('timeout', emitRequestTimeout);
     });
   }
-  // Remove socket timeout listener after response end.
-  req.once('response', (res) => {
-    res.once('end', () => {
-      req.socket.removeListener('timeout', emitRequestTimeout);
-    });
-  });
 }
 
 ClientRequest.prototype.onSocket = function onSocket(socket) {