Remove explicit interface versions of dartdoc files.

lib/html/doc/interface/SVGPointList.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 SVGPointList
-interface SVGPointList {
-
-  /** @domName SVGPointList.numberOfItems */
-  final int numberOfItems;
-
-  /** @domName SVGPointList.appendItem */
-  SVGPoint appendItem(SVGPoint item);
-
-  /** @domName SVGPointList.clear */
-  void clear();
-
-  /** @domName SVGPointList.getItem */
-  SVGPoint getItem(int index);
-
-  /** @domName SVGPointList.initialize */
-  SVGPoint initialize(SVGPoint item);
-
-  /** @domName SVGPointList.insertItemBefore */
-  SVGPoint insertItemBefore(SVGPoint item, int index);
-
-  /** @domName SVGPointList.removeItem */
-  SVGPoint removeItem(int index);
-
-  /** @domName SVGPointList.replaceItem */
-  SVGPoint replaceItem(SVGPoint item, int index);
-}