Implement automatically generated constructors for frog and dartium dart:html

client/html/generated/html/dartium/_EventSourceFactoryProvider.dart

Index: client/html/generated/html/dartium/_EventSourceFactoryProvider.dart
diff --git a/client/html/generated/html/interface/AudioElement.dart b/client/html/generated/html/dartium/_EventSourceFactoryProvider.dart
similarity index 63%
copy from client/html/generated/html/interface/AudioElement.dart
copy to client/html/generated/html/dartium/_EventSourceFactoryProvider.dart
index 42a2a861a2bd9563c017d6b0ab2cf33bcb0d6d3e..4e5f590d94b3e8dcfb04679271f617659e613cdd 100644
--- a/client/html/generated/html/interface/AudioElement.dart
+++ b/client/html/generated/html/dartium/_EventSourceFactoryProvider.dart
@@ -2,7 +2,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// WARNING: Do not edit - generated code.
-
-interface AudioElement extends MediaElement {
+class _EventSourceFactoryProvider {
+  factory EventSource(String scriptUrl) =>
+      _wrap(new dom.EventSource(scriptUrl));
 }