Constructs the Config factory.
Drupal\Core\Config\StorageInterface $storage: The storage controller object to use for reading and writing configuration data.
Symfony\Component\EventDispatcher\EventDispatcher: An event dispatcher instance to use for configuration events.
public function __construct(StorageInterface $storage, EventDispatcher $event_dispatcher) {
$this->storage = $storage;
$this->eventDispatcher = $event_dispatcher;
}