schema.default value used for render array type fields

jsonform/gadget_json_generated_form_child.js

@@ -639,6 +639,13 @@
       }
     }
 
+    if (json_document === undefined) {
+      if (schema.hasOwnProperty('default')) {
+        json_document = schema.default;
+        gadget.props.changed = true;
+      }
+    }
+
     // XXX add failback rendering if json_document not array
     // input = render_textarea(schema, default_value, "array");
     return RSVP.Queue()