/**
* Outputs all the given headers and retrieves the header suggestions from the renderer.
* Specific RenderSurfaces may override this function so to decide what to do with the headers.
*/
protected function outputHeaders(\System\Output\Renderer $renderer)
{
$headers = $this->getHeaders();
$headers->combine($renderer->getHeaderSuggestions());
foreach ($headers as $header) {
header($header);
}
}
