Remove explicit interface versions of dartdoc files.

lib/html/doc/interface/AppletElement.dartdoc

-// 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 HTMLAppletElement
-interface AppletElement extends Element {
-
-  /** @domName HTMLAppletElement.align */
-  String align;
-
-  /** @domName HTMLAppletElement.alt */
-  String alt;
-
-  /** @domName HTMLAppletElement.archive */
-  String archive;
-
-  /** @domName HTMLAppletElement.code */
-  String code;
-
-  /** @domName HTMLAppletElement.codeBase */
-  String codeBase;
-
-  /** @domName HTMLAppletElement.height */
-  String height;
-
-  /** @domName HTMLAppletElement.hspace */
-  String hspace;
-
-  /** @domName HTMLAppletElement.name */
-  String name;
-
-  /** @domName HTMLAppletElement.object */
-  String object;
-
-  /** @domName HTMLAppletElement.vspace */
-  String vspace;
-
-  /** @domName HTMLAppletElement.width */
-  String width;
-}