permettre le retour des résultats même si aucun groupe n'est définit

src/APIBundle/Controller/MasterAPIController.php

@@ -16,11 +16,14 @@ abstract class MasterAPIController extends MasterController
      * @param array $groups
      * @return JsonResponse
      */
-    protected function api($data, $status = 200, $groups = array())
+    protected function api($data, $status = 200, $groups = null)
     {
         $serializer = $this->get('jms_serializer');
-        $serialized = $serializer->serialize($data, 'json',
-            SerializationContext::create()->setGroups($groups));
+        $serialized = $serializer->serialize(
+            $data,
+            'json',
+            $groups !== null ? SerializationContext::create()->setGroups($groups) : null
+        );
 
         return new JsonResponse($serialized, $status, array(), true);
     }