Regenerate dart:html

lib/dom/frog/dom_frog.dart

Index: lib/dom/frog/dom_frog.dart
diff --git a/lib/dom/frog/dom_frog.dart b/lib/dom/frog/dom_frog.dart
index 9d67d688bfdb5487b441bc6395273032e17514dc..40da1927968c00d12e746aed17de827c2787a0c8 100644
--- a/lib/dom/frog/dom_frog.dart
+++ b/lib/dom/frog/dom_frog.dart
@@ -4281,7 +4281,7 @@ class _IDBDatabaseJs extends _EventTargetJs implements IDBDatabase native "*IDBD
 
   _IDBVersionChangeRequestJs setVersion(String version) native;
 
-  _IDBTransactionJs transaction(storeName_OR_storeNames, [int mode = null]) native;
+  _IDBTransactionJs transaction(storeName_OR_storeNames, int mode) native;
 }
 
 class _IDBDatabaseExceptionJs extends _DOMTypeJs implements IDBDatabaseException native "*IDBDatabaseException" {
@@ -17244,7 +17244,7 @@ interface IDBDatabase extends EventTarget {
 
   IDBVersionChangeRequest setVersion(String version);
 
-  IDBTransaction transaction(storeName_OR_storeNames, [int mode]);
+  IDBTransaction transaction(storeName_OR_storeNames, int mode);
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a