[gen4] key not working

[kevinresol]

class Main extends coconut.ui.View {
  static function main() {
    coconut.Ui.hxx('<Main/>').renderInto(js.Browser.document.body);
  }
  function render() '<div><Foo/></div>';
}

class Foo extends coconut.ui.View {
    @:state var key:String = '1';
    function render() '<div key=${key}/>';
    override function viewDidMount() key = '2';
}

See error in console:

 TypeError: Cannot read property 'insertBefore' of null

[back2dos]

Fixed.