Remove generated directories with 100s of files.

client/dom/generated/src/wrapping/_ProgressEventWrappingImplementation.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 _ProgressEventWrappingImplementation extends _EventWrappingImplementation implements ProgressEvent {
-  _ProgressEventWrappingImplementation() : super() {}
-
-  static create__ProgressEventWrappingImplementation() native {
-    return new _ProgressEventWrappingImplementation();
-  }
-
-  bool get lengthComputable() { return _get_lengthComputable(this); }
-  static bool _get_lengthComputable(var _this) native;
-
-  int get loaded() { return _get_loaded(this); }
-  static int _get_loaded(var _this) native;
-
-  int get total() { return _get_total(this); }
-  static int _get_total(var _this) native;
-
-  String get typeName() { return "ProgressEvent"; }
-}