federatedProviderShouldImmediatelyRedirect() {
    const immediateFederatedRedirect = !!this.config_.get(
        'immediateFederatedRedirect');
    const providers = this.getProviders();
    const signInFlow = this.getSignInFlow();
    return immediateFederatedRedirect &&
        providers.length == 1 &&
        idp.isFederatedSignInMethod(providers[0]) &&
        signInFlow == Config.SignInFlow.REDIRECT;
  }
Determines whether to show the 'nascar' sign-in buttons screen or
immediately redirect to the provider's site when there is only a single
federated provider in signInOptions. In order for this option to take
effect, the signInOptions must only hold a single federated provider (like
'google.com') and signInFlow must be set to 'redirect'.
@return {boolean} Whether to skip the 'nascar' screen or not.