Version 1.2.0-dev.3.1

sdk/lib/_internal/lib/isolate_helper.dart

Index: sdk/lib/_internal/lib/isolate_helper.dart
===================================================================
--- sdk/lib/_internal/lib/isolate_helper.dart	(revision 32236)
+++ sdk/lib/_internal/lib/isolate_helper.dart	(working copy)
@@ -1043,7 +1043,7 @@
 }
 
 /** Abstract visitor for dart objects that can be sent as isolate messages. */
-class _MessageTraverser {
+abstract class _MessageTraverser {
 
   _MessageTraverserVisitedMap _visited;
   _MessageTraverser() : _visited = new _MessageTraverserVisitedMap();
@@ -1167,7 +1167,7 @@
 }
 
 /** Deserializes arrays created with [_Serializer]. */
-class _Deserializer {
+abstract class _Deserializer {
   Map<int, dynamic> _deserialized;
 
   _Deserializer();