Cookie method causes an exception when called with no options

[Nane Kratzke]

Cookie method causes an exeception when called with no options.

app.get("/formular").listen((Request req) {
      req.response.cookie('test', 'example');
      req.response.send("something");
});

Above causes exception. The following works:

app.get("/formular").listen((Request req) {
      req.response.cookie('test', 'example', {});
      req.response.send("something");
});