Remove generated directories with 100s of files.

client/html/generated/html/interface/SVGMaskElement.dart

Index: client/html/generated/html/interface/SVGMaskElement.dart
diff --git a/client/html/generated/html/interface/SVGMaskElement.dart b/client/html/generated/html/interface/SVGMaskElement.dart
deleted file mode 100644
index f3cc728ea5381de185433134462e5991c0aa78c6..0000000000000000000000000000000000000000
--- a/client/html/generated/html/interface/SVGMaskElement.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 SVGMaskElement extends SVGElement, SVGTests, SVGLangSpace, SVGExternalResourcesRequired, SVGStylable {
-
-  final SVGAnimatedLength height;
-
-  final SVGAnimatedEnumeration maskContentUnits;
-
-  final SVGAnimatedEnumeration maskUnits;
-
-  final SVGAnimatedLength width;
-
-  final SVGAnimatedLength x;
-
-  final SVGAnimatedLength y;
-}