Sets the request on the language manager.
\Symfony\Component\HttpKernel\Event\GetResponseEvent $event: The Event to process.
public function onKernelRequestLanguage(GetResponseEvent $event) {
if ($event
->getRequestType() == HttpKernelInterface::MASTER_REQUEST) {
$this->languageManager
->setRequest($event
->getRequest());
// After the language manager has initialized, set the default langcode
// for the string translations.
$langcode = $this->languageManager
->getLanguage(Language::TYPE_INTERFACE)->langcode;
$this->translation
->setDefaultLangcode($langcode);
}
}