Remove explicit interface versions of dartdoc files.

lib/html/doc/interface/HTMLOptionsCollection.dartdoc

Index: lib/html/doc/interface/HTMLOptionsCollection.dartdoc
diff --git a/lib/html/doc/interface/HTMLOptionsCollection.dartdoc b/lib/html/doc/interface/HTMLOptionsCollection.dartdoc
deleted file mode 100644
index c372e04d76e403a1ecfed01076e2e60de54405d9..0000000000000000000000000000000000000000
--- a/lib/html/doc/interface/HTMLOptionsCollection.dartdoc
+++ /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:
-//   This file contains documentation that is merged into the real source.
-//   Do not make code changes here.
-
-/// @domName HTMLOptionsCollection
-interface HTMLOptionsCollection extends HTMLCollection {
-
-  /** @domName HTMLOptionsCollection.length */
-  int length;
-
-  /** @domName HTMLOptionsCollection.selectedIndex */
-  int selectedIndex;
-
-  /** @domName HTMLOptionsCollection.remove */
-  void remove(int index);
-}