vue_activity location: add NewLocation fields, submit activity form with hidden field (+)

src/Bundle/ChillMainBundle/Entity/Location.php

@@ -9,10 +9,14 @@ use Chill\MainBundle\Validation\Constraint\PhonenumberConstraint;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Component\Serializer\Annotation as Serializer;
 use Symfony\Component\Validator\Constraints as Assert;
+use Symfony\Component\Serializer\Annotation\DiscriminatorMap;
 
 /**
  * @ORM\Table(name="chill_main_location")
  * @ORM\Entity(repositoryClass=LocationRepository::class)
+ * @DiscriminatorMap(typeProperty="type", mapping={
+ *  "location"=Location::class
+ *  })
  */
 class Location implements TrackCreationInterface, TrackUpdateInterface
 {