Remove generated directories with 100s of files.

client/dom/generated/src/wrapping/_DOMImplementationWrappingImplementation.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 _DOMImplementationWrappingImplementation extends DOMWrapperBase implements DOMImplementation {
-  _DOMImplementationWrappingImplementation() : super() {}
-
-  static create__DOMImplementationWrappingImplementation() native {
-    return new _DOMImplementationWrappingImplementation();
-  }
-
-  CSSStyleSheet createCSSStyleSheet(String title, String media) {
-    return _createCSSStyleSheet(this, title, media);
-  }
-  static CSSStyleSheet _createCSSStyleSheet(receiver, title, media) native;
-
-  Document createDocument(String namespaceURI, String qualifiedName, DocumentType doctype) {
-    return _createDocument(this, namespaceURI, qualifiedName, doctype);
-  }
-  static Document _createDocument(receiver, namespaceURI, qualifiedName, doctype) native;
-
-  DocumentType createDocumentType(String qualifiedName, String publicId, String systemId) {
-    return _createDocumentType(this, qualifiedName, publicId, systemId);
-  }
-  static DocumentType _createDocumentType(receiver, qualifiedName, publicId, systemId) native;
-
-  HTMLDocument createHTMLDocument(String title) {
-    return _createHTMLDocument(this, title);
-  }
-  static HTMLDocument _createHTMLDocument(receiver, title) native;
-
-  bool hasFeature(String feature, String version) {
-    return _hasFeature(this, feature, version);
-  }
-  static bool _hasFeature(receiver, feature, version) native;
-
-  String get typeName() { return "DOMImplementation"; }
-}