http: prevent aborted event when already completed

When socket is closed on a response for a request that is being piped to
a stream there is a condition where aborted event will be fired to http
client when socket is closing and the incomingMessage stream is still
set to readable.
We need a check for request being complete and to only raise the
'aborted' event on the http client if we have not yet completed reading
the response from the server.
Fixes: #18756
PR-URL: #18999
Reviewed-By: Shingo Inoue <leko.noor@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: billywhizz

lib/_http_client.js

@@ -353,7 +353,7 @@ function socketCloseListener() {
 varparser=socket.parser;
 if(req.res&&req.res.readable){
 // Socket closed before we emitted 'end' below.
-req.res.emit('aborted');
+if(!req.res.complete)req.res.emit('aborted');
 varres=req.res;
 res.on('end',function(){
 res.emit('close');