Fix parsing of DOMString[] in IDL

client/dom/generated/src/frog/IDBDatabase.dart

 
 class _IDBDatabaseJs extends _DOMTypeJs implements IDBDatabase native "*IDBDatabase" {
 
   final String name;
 
   EventListener onabort;
 
   EventListener onerror;
 
   EventListener onversionchange;
 
   final String version;
 
   void addEventListener(String type, EventListener listener, [bool useCapture = null]) native;
 
   void close() native;
 
   _IDBObjectStoreJs createObjectStore(String name) native;
 
   void deleteObjectStore(String name) native;
 
   bool dispatchEvent(_EventJs evt) native;
 
   void removeEventListener(String type, EventListener listener, [bool useCapture = null]) native;
 
   _IDBVersionChangeRequestJs setVersion(String version) native;
 
-  _IDBTransactionJs transaction(String storeName, int mode) native;
+  _IDBTransactionJs transaction(String storeName, [int mode = null]) native;
 }