Merge pull request #3179 from rande/fix_serialisation_with_closure

fix serialisation with closure

Admin/Admin.php

@@ -1367,6 +1367,7 @@ abstract class Admin implements AdminInterface, DomainObjectInterface
                     $extension->validate($admin, $errorElement, $object);
                 }
             },
+            'serializingWarning' => true,
         )));
     }
 

composer.json

@@ -34,7 +34,7 @@
         "twig/extensions": "~1.0",
         "sonata-project/exporter": "~1.0",
         "sonata-project/block-bundle": "~2.3",
-        "sonata-project/core-bundle": "^2.3.2",
+        "sonata-project/core-bundle": "^2.3.6",
         "doctrine/common": "~2.2",
         "doctrine/inflector": "~1.0",
         "knplabs/knp-menu-bundle": ">=2.0,<3.0.0",