Remove generated directories with 100s of files.

client/dom/generated/src/wrapping/_CounterWrappingImplementation.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 _CounterWrappingImplementation extends DOMWrapperBase implements Counter {
-  _CounterWrappingImplementation() : super() {}
-
-  static create__CounterWrappingImplementation() native {
-    return new _CounterWrappingImplementation();
-  }
-
-  String get identifier() { return _get_identifier(this); }
-  static String _get_identifier(var _this) native;
-
-  String get listStyle() { return _get_listStyle(this); }
-  static String _get_listStyle(var _this) native;
-
-  String get separator() { return _get_separator(this); }
-  static String _get_separator(var _this) native;
-
-  String get typeName() { return "Counter"; }
-}