Add corelib tests

test/codegen/corelib/date_time8_test.dart

Index: test/codegen/corelib/date_time8_test.dart
diff --git a/test/codegen/corelib/date_time8_test.dart b/test/codegen/corelib/date_time8_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..85d573f56b81a5fd582ad825c8f655f64e01c9b6
--- /dev/null
+++ b/test/codegen/corelib/date_time8_test.dart
@@ -0,0 +1,22 @@
+// 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
+// BSD-style license that can be found in the LICENSE file.
+
+import "package:expect/expect.dart";
+
+// Make sure the year 0 is correctly printed.
+
+testUtc() {
+  var d = new DateTime.utc(0, 1, 1);
+  Expect.equals("0000-01-01 00:00:00.000Z", d.toString());
+}
+
+testLocal() {
+  var d = new DateTime(0, 1, 1);
+  Expect.equals("0000-01-01 00:00:00.000", d.toString());
+}
+
+main() {
+  testUtc();
+  testLocal();
+}