Request::setTrustedHeaderName PHP Method

        public static function setTrustedHeaderName($key, $value)
        {
            //Method inherited from \Symfony\Component\HttpFoundation\Request
            return \Illuminate\Http\Request::setTrustedHeaderName($key, $value);
        }

 * Setup the core service groups.
 * ----------------------------------------------------------------------------
 */
$list = new ProviderList($cms);
// Register events first so that they can be used by other providers.
$list->registerProvider($config->get('app.providers.core_events'));
// Register all other providers
$list->registerProviders($config->get('app.providers'));
/**
 * ----------------------------------------------------------------------------
 * Set trusted proxies and headers for the request
 * ----------------------------------------------------------------------------
 */
if ($proxyHeaders = $config->get('concrete.security.trusted_proxies.headers')) {
    foreach ($proxyHeaders as $key => $value) {
        Request::setTrustedHeaderName($key, $value);
    }
}
if ($trustedProxiesIps = $config->get('concrete.security.trusted_proxies.ips')) {
    Request::setTrustedProxies($trustedProxiesIps);
}
/**
 * ----------------------------------------------------------------------------
 * Legacy Definitions
 * ----------------------------------------------------------------------------
 */
define('APP_VERSION', $config->get('concrete.version'));
define('APP_CHARSET', $config->get('concrete.charset'));
try {
    define('BASE_URL', \Core::getApplicationURL());
} catch (\Exception $x) {