Remove generated directories with 100s of files.

client/dom/generated/src/wrapping/_HTMLLIElementWrappingImplementation.dart

-// 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.
-
-// WARNING: Do not edit - generated code.
-
-class _HTMLLIElementWrappingImplementation extends _HTMLElementWrappingImplementation implements HTMLLIElement {
-  _HTMLLIElementWrappingImplementation() : super() {}
-
-  static create__HTMLLIElementWrappingImplementation() native {
-    return new _HTMLLIElementWrappingImplementation();
-  }
-
-  String get type() { return _get_type(this); }
-  static String _get_type(var _this) native;
-
-  void set type(String value) { _set_type(this, value); }
-  static void _set_type(var _this, String value) native;
-
-  int get value() { return _get_value(this); }
-  static int _get_value(var _this) native;
-
-  void set value(int value) { _set_value(this, value); }
-  static void _set_value(var _this, int value) native;
-
-  String get typeName() { return "HTMLLIElement"; }
-}