Get rid of DOMWrapperBase and DOMTypeBase.

lib/dom/src/native_DOMWrapperBase.dart

Index: lib/dom/src/native_DOMWrapperBase.dart
diff --git a/lib/dom/src/native_DOMWrapperBase.dart b/lib/dom/src/native_DOMWrapperBase.dart
deleted file mode 100644
index 170679742543cb18021009703b03e1dfcc92d622..0000000000000000000000000000000000000000
--- a/lib/dom/src/native_DOMWrapperBase.dart
+++ /dev/null
@@ -1,7 +0,0 @@
-// Copyright (c) 2011, 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.
-
-// FIXME: get rid of _DOMWrapperBase.
-class _DOMWrapperBase extends NativeFieldWrapperClass1 {
-}