FosUser creation formulaire /register et /pro/register

Bonjour,

Voila je rencontre un petit problème avec mon code, J'ai suivis tuto de jeffcoding sur youtube, mais je suis sur symfony 3.4 et une erreur est levée pour /pro/register alors que /register fonctionne parfaitement.

Ce que je fais

namespace AppBundle\Entity;

use FOS\UserBundle\Model\User as BaseUser;
use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * @ORM\Entity
 * @ORM\Table(name="fos_user")
 */
class User extends BaseUser
{
    /**
     * @ORM\Id
     * @ORM\Column(type="integer")
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    protected $id;

    /**
     * @var string
     * @ORM\Column(name="firstName", type="string", length=255)
     */
    private $firstName;

    /**
     * @var string
     * @ORM\Column(name="lastName", type="string", length=255)
     */
    private $lastName;

    /**
     * @var string
     * @ORM\Column(name="corporateName", type="string", length=255, nullable=true)
     */
    private $corporateName;

    /**
     * @var string
     * @ORM\Column(name="legalForm", type="string", length=255, nullable=true)
     */
    private $legalForm;

    /**
     * @var int
     * @ORM\Column(name="tva", type="integer", nullable=true)
     */
    private $tva;

    /**
     * @var string
     * @ORM\Column(name="street", type="string", length=255)
     */
    private $street;

    /**
     * @var int
     * @ORM\Column(name="number", type="integer")
     */
    private $number;

    /**
     * @var string
     * @ORM\Column(name="box", type="string", nullable=true)
     */
    private $box;

    /**
     * @var int
     * @ORM\Column(name="postalCode", type="integer")
     */
    private $postalCode;

    /**
     * @var string
     * @ORM\Column(name="city", type="string", length=255)
     */
    private $city;

    /**
     * @var int
     * @ORM\Column(name="nbrchildren", type="integer", nullable=true)
     */
    private $nbrchildren;

    public function __construct()
    {
        parent::__construct();
        // your own logic
    }

    /**
     * Set firstName
     *
     * @param string $firstName
     *
     * @return User
     */
    public function setFirstName($firstName)
    {
        $this->firstName = $firstName;

        return $this;
    }

    /**
     * Get firstName
     *
     * @return string
     */
    public function getFirstName()
    {
        return $this->firstName;
    }

    /**
     * Set lastName
     *
     * @param string $lastName
     *
     * @return User
     */
    public function setLastName($lastName)
    {
        $this->lastName = $lastName;

        return $this;
    }

    /**
     * Get lastName
     *
     * @return string
     */
    public function getLastName()
    {
        return $this->lastName;
    }

    /**
     * Set corporateName
     *
     * @param string $corporateName
     *
     * @return User
     */
    public function setCorporateName($corporateName)
    {
        $this->corporateName = $corporateName;

        return $this;
    }

    /**
     * Get corporateName
     *
     * @return string
     */
    public function getCorporateName()
    {
        return $this->corporateName;
    }

    /**
     * Set legalForm
     *
     * @param string $legalForm
     *
     * @return User
     */
    public function setLegalForm($legalForm)
    {
        $this->legalForm = $legalForm;

        return $this;
    }

    /**
     * Get legalForm
     *
     * @return string
     */
    public function getLegalForm()
    {
        return $this->legalForm;
    }

    /**
     * Set tva
     *
     * @param integer $tva
     *
     * @return User
     */
    public function setTva($tva)
    {
        $this->tva = $tva;

        return $this;
    }

    /**
     * Get tva
     *
     * @return integer
     */
    public function getTva()
    {
        return $this->tva;
    }

    /**
     * Set street
     *
     * @param string $street
     *
     * @return User
     */
    public function setStreet($street)
    {
        $this->street = $street;

        return $this;
    }

    /**
     * Get street
     *
     * @return string
     */
    public function getStreet()
    {
        return $this->street;
    }

    /**
     * Set number
     *
     * @param integer $number
     *
     * @return User
     */
    public function setNumber($number)
    {
        $this->number = $number;

        return $this;
    }

    /**
     * Get number
     *
     * @return integer
     */
    public function getNumber()
    {
        return $this->number;
    }

    /**
     * Set box
     *
     * @param integer $box
     *
     * @return User
     */
    public function setBox($box)
    {
        $this->box = $box;

        return $this;
    }

    /**
     * Get box
     *
     * @return integer
     */
    public function getBox()
    {
        return $this->box;
    }

    /**
     * Set postalCode
     *
     * @param integer $postalCode
     *
     * @return User
     */
    public function setPostalCode($postalCode)
    {
        $this->postalCode = $postalCode;

        return $this;
    }

    /**
     * Get postalCode
     *
     * @return integer
     */
    public function getPostalCode()
    {
        return $this->postalCode;
    }

    /**
     * Set city
     *
     * @param string $city
     *
     * @return User
     */
    public function setCity($city)
    {
        $this->city = $city;

        return $this;
    }

    /**
     * Get city
     *
     * @return string
     */
    public function getCity()
    {
        return $this->city;
    }

    /**
     * Set nbrchildren
     *
     * @param integer $nbrchildren
     *
     * @return User
     */
    public function setNbrchildren($nbrchildren)
    {
        $this->nbrchildren = $nbrchildren;

        return $this;
    }

    /**
     * Get nbrchildren
     *
     * @return integer
     */
    public function getNbrchildren()
    {
        return $this->nbrchildren;
    }
}

namespace AppBundle\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;

class RegistrationType extends AbstractType
{

    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder

            ->add('lastName', null, ["label"=>"Nom"])
            ->add('firstName', null, ["label"=>"Prénom"])
            ->add('street', null, ["label"=>"Rue"])
            ->add('number', null, ["label"=>"Numéro"])
            ->add('box', null, ["label"=>"Boîte"])
            ->add('postalCode', null, ["label"=>"Code Postal"])
            ->add('city', null, ["label"=>"Ville"])
            ->add('nbrchildren', null, ["label"=>"Nombre(s) d'enfant(s)"])
        ;
    }

    public function getParent()
    {
        return 'FOS\UserBundle\Form\Type\RegistrationFormType';
    }

    public function getBlockPrefix()
    {
        return 'app_user_registration';
    }
}

namespace AppBundle\Form;

use FOS\UserBundle\Form\Type\RegistrationFormType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\Form\Extension\Core\Type\TextType;
use Symfony\Component\Form\Extension\Core\Type\IntegerType;

class ProRegistrationType extends RegistrationFormType
{

    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('corporateName', textType::class, ["label"=>"Nom de l'entreprise"])
            ->add('legalForm', textType::class, ["label"=>"Forme juridique"])
            ->add('tva', textType::class)
            ->add('lastName', textType::class)
            ->add('firstName', textType::class)
            ->add('street', textType::class)
            ->add('number', IntegerType::class)
            ->add('box', textType::class)
            ->add('postalCode', IntegerType::class)
            ->add('city', textType::class)
            ->add('nbrchildren')

        ;
    }

    public function getBlockPrefix()
    {
        return 'app_user_pro_registration';
    }
}

namespace AppBundle\Controller;

use FOS\UserBundle\FOSUserEvents;
use FOS\UserBundle\Event\FormEvent;
use FOS\UserBundle\Event\GetResponseUserEvent;
use FOS\UserBundle\Event\FilterUserResponseEvent;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\RedirectResponse;
use FOS\UserBundle\Controller\RegistrationController as BaseController;
use AppBundle\Form\ProRegistrationType;
use Symfony\Component\Routing\Annotation\Route;
use FOS\UserBundle\Form\Factory\FactoryInterface;
use FOS\UserBundle\Model\UserManagerInterface;
use Symfony\Component\EventDispatcher\EventDispatcherInterface;

class RegistrationController extends BaseController
{
    /**
     * @Route("/pro/register", name="app_user_pro_register")
     */
    public function registerProAction(Request $request)
    {

        /** @var $formFactory FactoryInterface */
        $formFactory = $this->get('form.factory');
        /** @var $userManager UserManagerInterface */
        $userManager = $this->get('fos_user.user_manager');
        /** @var $dispatcher EventDispatcherInterface */
        $dispatcher = $this->get('event_dispatcher');

        $user = $userManager->createUser();
        $user->setEnabled(true);
        $user->addRole('ROLE_PRO');

        $event = new GetResponseUserEvent($user, $request);
        $dispatcher->dispatch(FOSUserEvents::REGISTRATION_INITIALIZE, $event);

        if (null !== $event->getResponse()) {
            return $event->getResponse();
        }

        //$form = $formFactory->createForm();
        $form = $formFactory->create(new ProRegistrationType($this->container->getParameter("fos_user.model.user.class")));
        $form->setData($user);

        $form->handleRequest($request);

        if ($form->isSubmitted()) {
            if ($form->isValid()) {
                $event = new FormEvent($form, $request);
                $dispatcher->dispatch(FOSUserEvents::REGISTRATION_SUCCESS, $event);

                $userManager->updateUser($user);

                if (null === $response = $event->getResponse()) {
                    $url = $this->generateUrl('fos_user_registration_confirmed');
                    $response = new RedirectResponse($url);
                }

                $dispatcher->dispatch(FOSUserEvents::REGISTRATION_COMPLETED, new FilterUserResponseEvent($user, $request, $response));

                return $response;
            }

            $event = new FormEvent($form, $request);
            $dispatcher->dispatch(FOSUserEvents::REGISTRATION_FAILURE, $event);

            if (null !== $response = $event->getResponse()) {
                return $response;
            }
        }

        return $this->render('@Appbundle/Registration/register.html.twig', array(
            'form' => $form->createView(),
        ));
    }
}

    app.form.registration:
        class: AppBundle\Form\RegistrationType
        tags:
            - { name: form.type, alias: app_user_registration }

    app_user_pro.pro.registration:
        class: AppBundle\Form\ProRegistrationType
        arguments: [fos_user.model.user.class]
        tags :
            - { name: form.type, alias: app_user_pro_registration }

Ce que je veux

Mon but est simplement que sur les 2 formulaires, les infos communes s'affichent, et les infos propre à chaque condition, à savoir user particulier, et user professionnel.

Ce que j'obtiens

Voici l'erreur:
Expected argument of type "string", "AppBundle\Form\ProRegistrationType" given

En cherchant l'erreur viens de la ligne : $form = $formFactory->create(new ParentRegistrationType($this->container->getParameter('fos_user.model.user.class')));
du contrôleur qui n'est plus actualité dans symfony 3.

Je ne parviens pas à y remedier.... Si quelq'un a une idée, je suis preneur.......

Merci d'avance à vous tous ;)

Personne ne peux m'aider? .....