public function validateNameMail(array &$form, FormStateInterface $form_state) {
    $user_blocked = social_user_is_blocked($form_state->getValue('name_or_mail'));
    if ($user_blocked) {
      // Blocked in user administration.
      if (!$form_state->get('uid')) {
        $this->setGeneralErrorMessage($form, $form_state);
      }
      else {
        $form_state->setErrorByName('name_or_mail', $this->t('The username %name has not been activated or is blocked.', ['%name' => $form_state->getValue('name_or_mail')]));
      }
    }
  }