Revert "Remove Expect from core library."

This reverts commit 19755.

Review URL: https://codereview.chromium.org//12743005

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/yaml@19756 260f80e4-7a28-3924-810f-c04153c831b5
diff --git a/test/yaml_test.dart b/test/yaml_test.dart
index 6013dc9..901bd3d 100644
--- a/test/yaml_test.dart
+++ b/test/yaml_test.dart
@@ -4,8 +4,6 @@
 
 library yaml_test;
 
-// TODO(rnystrom): rewrite tests so that they don't need "Expect".
-import "package:expect/expect.dart";
 import 'package:unittest/unittest.dart';
 import 'package:yaml/yaml.dart';
 import 'package:yaml/deep_equals.dart';