Add some sweet XML classes.

client/tests/client/html/util.dart

Index: client/tests/client/html/util.dart
diff --git a/client/tests/client/html/util.dart b/client/tests/client/html/util.dart
new file mode 100644
index 0000000000000000000000000000000000000000..22d2c74ec0919c12addce4d5d4103bb6a035ddf0
--- /dev/null
+++ b/client/tests/client/html/util.dart
@@ -0,0 +1,15 @@
+// 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.
+
+void expectUnsupported(void fn()) =>
+  Expect.throws(fn, (e) => e is UnsupportedOperationException);
+
+void expectEmptyRect(ClientRect rect) {
+  Expect.equals(0, rect.bottom);
+  Expect.equals(0, rect.top);
+  Expect.equals(0, rect.left);
+  Expect.equals(0, rect.right);
+  Expect.equals(0, rect.height);
+  Expect.equals(0, rect.width);
+}