Remove generated directories with 100s of files.

client/dom/generated/src/wrapping/_ArrayBufferWrappingImplementation.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 _ArrayBufferWrappingImplementation extends DOMWrapperBase implements ArrayBuffer {
-  _ArrayBufferWrappingImplementation() : super() {}
-
-  static create__ArrayBufferWrappingImplementation() native {
-    return new _ArrayBufferWrappingImplementation();
-  }
-
-  int get byteLength() { return _get_byteLength(this); }
-  static int _get_byteLength(var _this) native;
-
-  ArrayBuffer slice(int begin, [int end = null]) {
-    if (end === null) {
-      return _slice(this, begin);
-    } else {
-      return _slice_2(this, begin, end);
-    }
-  }
-  static ArrayBuffer _slice(receiver, begin) native;
-  static ArrayBuffer _slice_2(receiver, begin, end) native;
-
-  String get typeName() { return "ArrayBuffer"; }
-}