code: function() {
      var errorMessage =
          firebaseui.auth.widget.handler.common.getErrorMessage(emailExistsError);
      firebaseui.auth.ui.element.setValid(component.getEmailElement(), false);
      firebaseui.auth.ui.element.show(
          component.getEmailErrorElement(), errorMessage);
      component.getEmailElement().focus();
    }
docs: If a provider already exists, just display the error and focus the email element.