Error When Calling Function Via ng-click On AngularJS Controller?

The code can be viewed at http://ift.tt/1Ei84yz

In the login form, I call the currently simple login() function of the AuthController from ng-click on the button of the the login form. When I call this function, I get an error in the console that I cannot decipher. In FF, I get an "args is null" error. In Chrome, errors says "TypeError: Cannot read property '0' of null". Not sure how to debug this? Why doesn't it work?

PS: You can enter any username or password.