net: always invoke after-write callback

This is part of the streams API contract, and aligns
network sockets with other streams in this respect.

PR-URL: #24291
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Weijia Wang <starkwang@126.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: addaleax

lib/net.js

@@ -790,6 +790,8 @@ function afterWrite(status, handle, err) {
   // callback may come after call to destroy.
   if (self.destroyed) {
     debug('afterWrite destroyed');
+    if (this.callback)
+      this.callback(null);
     return;
   }
 

test/parallel/test-tls-invoke-queued.js

@@ -40,8 +40,8 @@ const server = tls.createServer({
     c.write('world!', null, common.mustCall(function() {
       c.destroy();
     }));
-    // Data on next _write() will be written but callback will not be invoked
-    c.write(' gosh', null, common.mustNotCall());
+    // Data on next _write() will be written, and the cb will still be invoked
+    c.write(' gosh', null, common.mustCall());
   }));
 
   server.close();