Remove generated directories with 100s of files.

client/dom/generated/src/wrapping/_AttrWrappingImplementation.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 _AttrWrappingImplementation extends _NodeWrappingImplementation implements Attr {
-  _AttrWrappingImplementation() : super() {}
-
-  static create__AttrWrappingImplementation() native {
-    return new _AttrWrappingImplementation();
-  }
-
-  bool get isId() { return _get_isId(this); }
-  static bool _get_isId(var _this) native;
-
-  String get name() { return _get_name(this); }
-  static String _get_name(var _this) native;
-
-  Element get ownerElement() { return _get_ownerElement(this); }
-  static Element _get_ownerElement(var _this) native;
-
-  bool get specified() { return _get_specified(this); }
-  static bool _get_specified(var _this) native;
-
-  String get value() { return _get_value(this); }
-  static String _get_value(var _this) native;
-
-  void set value(String value) { _set_value(this, value); }
-  static void _set_value(var _this, String value) native;
-
-  String get typeName() { return "Attr"; }
-}