Remove generated directories with 100s of files.

client/html/generated/html/interface/CSSMediaRule.dart

Index: client/html/generated/html/interface/CSSMediaRule.dart
diff --git a/client/html/generated/html/interface/CSSMediaRule.dart b/client/html/generated/html/interface/CSSMediaRule.dart
deleted file mode 100644
index be58516e8b2fb4243bb4bc820430b286bb9d0549..0000000000000000000000000000000000000000
--- a/client/html/generated/html/interface/CSSMediaRule.dart
+++ /dev/null
@@ -1,16 +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 CSSMediaRule extends CSSRule {
-
-  final CSSRuleList cssRules;
-
-  final MediaList media;
-
-  void deleteRule(int index);
-
-  int insertRule(String rule, int index);
-}