common\Cookie::delete PHP Method

    public static function delete()
    {
        $domain = null;
        if (FrontendModel::getContainer()->has('request')) {
            $domain = '.' . FrontendModel::getContainer()->get('request')->getHost();
        }
        foreach (func_get_args() as $argument) {
            // multiple arguments are given
            if (is_array($argument)) {
                foreach ($argument as $key) {
                    self::delete($key);
                }
            } else {
                // delete the given cookie
                unset($_COOKIE[(string) $argument]);
                setcookie((string) $argument, null, 1, '/', $domain);
            }
        }
    }

 /**
  * Logout a profile.
  */
 public static function logout()
 {
     // delete session records
     FrontendModel::getContainer()->get('database')->delete('profiles_sessions', 'session_id = ?', array(\SpoonSession::getSessionId()));
     // set is_logged_in to false
     \SpoonSession::set('frontend_profile_logged_in', false);
     // delete cookie
     CommonCookie::delete('frontend_profile_secret_key');
 }