Remove generated directories with 100s of files.

client/html/generated/html/interface/DOMPlugin.dart

Index: client/html/generated/html/interface/DOMPlugin.dart
diff --git a/client/html/generated/html/interface/DOMPlugin.dart b/client/html/generated/html/interface/DOMPlugin.dart
deleted file mode 100644
index 9818043d208a843e249f68d5bc9df0a7744b4f42..0000000000000000000000000000000000000000
--- a/client/html/generated/html/interface/DOMPlugin.dart
+++ /dev/null
@@ -1,20 +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 DOMPlugin {
-
-  final String description;
-
-  final String filename;
-
-  final int length;
-
-  final String name;
-
-  DOMMimeType item(int index);
-
-  DOMMimeType namedItem(String name);
-}