anchor.diff:                s.setListening(read: false, write: false);
               });
               connecting.clear();
  -          }, error: (e) {
  +          }, error: (e, st) {
               timer.cancel();
               socket.close();
               // Keep first error, if present.
  
positive.code:           _controller.add(RawSocketEvent.closed);
            _controller.close();
          },
          error: zone.bindUnaryCallbackGuarded((e) {
            _controller.addError(e);
            _socket.close();
          }));
    }
  
negative.code:         bytes, (address as _InternetAddress)._in_addr, port);
      if (result is OSError) {
        OSError osError = result;
        StackTrace st = StackTrace.current;
        scheduleMicrotask(() => reportError(osError, st, "Send failed"));
        result = 0;
      }
      // TODO(ricow): Remove when we track internal and pipe uses.
  