Inject RouteMatchInterface to ContentEntityForm

use Drupal\Core\Routing\RouteMatchInterface;

/**
 * The current route match.
 *
 * @var \Drupal\Core\Routing\RouteMatchInterface
 */
protected $routeMatch;

/**
 * Constructs a PrivatemsgMessageForm object.
 *
 * @param \Drupal\Core\Entity\EntityRepositoryInterface $entity_repository
 *   The entity repository service.
 * @param \Drupal\Core\Entity\EntityTypeBundleInfoInterface $entity_type_bundle_info
 *   The entity type bundle service.
 * @param \Drupal\Component\Datetime\TimeInterface $time
 *   The time service.
 * @param \Drupal\Core\Routing\RouteMatchInterface $route_match
 *   The route match.
 */
public function __construct(EntityRepositoryInterface $entity_repository, EntityTypeBundleInfoInterface $entity_type_bundle_info, TimeInterface $time, RouteMatchInterface $route_match) {
 parent::__construct($entity_repository, $entity_type_bundle_info, $time);
 $this->routeMatch = $route_match;
}

/**
  * {@inheritdoc}
  */
public static function create(ContainerInterface $container) {
  return new static(
    $container->get('entity.repository'),
    $container->get('entity_type.bundle.info'),
    $container->get('datetime.time'),
    $container->get('current_route_match')
  );
}