Generate dummy dom to replace wrapping dom for dartc.

client/dom/src/dummy_GlobalProperties.dart

Index: client/dom/src/dummy_GlobalProperties.dart
diff --git a/client/dom/src/dummy_GlobalProperties.dart b/client/dom/src/dummy_GlobalProperties.dart
new file mode 100644
index 0000000000000000000000000000000000000000..a8ce2ad639f46a77df3122914d3f253ad5470179
--- /dev/null
+++ b/client/dom/src/dummy_GlobalProperties.dart
@@ -0,0 +1,10 @@
+// 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.
+
+Window get window() => _dummy();
+
+// TODO(vsm): Remove when prefixes are supported.
+Window get dom_window() => _dummy();
+
+Document get document() => _dummy();