New expectation functions plus convert old tests to use these.

tests/html/messageevent_test.dart

Index: tests/html/messageevent_test.dart
===================================================================
--- tests/html/messageevent_test.dart	(revision 8345)
+++ tests/html/messageevent_test.dart	(working copy)
@@ -9,13 +9,13 @@
   test('MessageEvent.initMessageEvent', () {
       final event = document.$dom_createEvent('MessageEvent');
       event.initMessageEvent('type', false, true, 'data', 'origin', 'lastEventId', window, []);
-      expect(event.type).equals('type');
-      expect(event.bubbles).equals(false);
-      expect(event.cancelable).equals(true);
-      expect(event.data).equals('data');
-      expect(event.origin).equals('origin');
-      expect(event.lastEventId).equals('lastEventId');
-      expect(event.source).same(window);
+      expect(event.type, equals('type'));
+      expect(event.bubbles, isFalse);
+      expect(event.cancelable, isTrue);
+      expect(event.data, equals('data'));
+      expect(event.origin, equals('origin'));
+      expect(event.lastEventId, equals('lastEventId'));
+      expect(event.source, same(window));
       // TODO(antonm): accessing ports is not supported yet.
   });
 }