reproduce bug when applying defaults

Author: Mathieu Rochette

tests/Constraints/DefaultPropertiesTest.php

@@ -149,6 +149,11 @@ public function getValidTests()
                 '{"items":[{"default":null}]}',
                 '[null]'
             ),
+            array(// #21 items might be an array of schema (instead of an array of schema)
+                '[{}]',
+                '{"items":{"properties":{"propertyOne":{"default":"valueOne"}},"required":[]}}',
+                '[{"propertyOne":"valueOne"}]'
+            ),
         );
     }