Remove generated directories with 100s of files.

client/html/generated/html/interface/ElementTraversal.dart

Index: client/html/generated/html/interface/ElementTraversal.dart
diff --git a/client/html/generated/html/interface/ElementTraversal.dart b/client/html/generated/html/interface/ElementTraversal.dart
deleted file mode 100644
index e6c670cb2ee0c4adb40c749a4a2ab566abd0a501..0000000000000000000000000000000000000000
--- a/client/html/generated/html/interface/ElementTraversal.dart
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright (c) 2012, 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.
-
-interface ElementTraversal {
-
-  final int childElementCount;
-
-  final Element firstElementChild;
-
-  final Element lastElementChild;
-
-  final Element nextElementSibling;
-
-  final Element previousElementSibling;
-}