Remove generated directories with 100s of files.

client/dom/generated/src/wrapping/_WebGLDebugShadersWrappingImplementation.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 _WebGLDebugShadersWrappingImplementation extends DOMWrapperBase implements WebGLDebugShaders {
-  _WebGLDebugShadersWrappingImplementation() : super() {}
-
-  static create__WebGLDebugShadersWrappingImplementation() native {
-    return new _WebGLDebugShadersWrappingImplementation();
-  }
-
-  String getTranslatedShaderSource(WebGLShader shader) {
-    return _getTranslatedShaderSource(this, shader);
-  }
-  static String _getTranslatedShaderSource(receiver, shader) native;
-
-  String get typeName() { return "WebGLDebugShaders"; }
-}