modules/user/views_handler_filter_user_roles.inc

<?php
class views_handler_filter_user_roles extends views_handler_filter_many_to_one {
  function get_value_options() {
    $this->value_options = user_roles(TRUE);
    unset($this->value_options[DRUPAL_AUTHENTICATED_RID]);
  }

  function operators() {
    $operators = parent::operators();
    $operators['empty']['title'] = t("Only has the 'authenticated user' role");
    $operators['not empty']['title'] = t("Has roles in addition to 'authenticated user'");
    return $operators;
  }
}