Remove explicit interface versions of dartdoc files.

lib/html/doc/interface/SVGPathSegArcAbs.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 SVGPathSegArcAbs
-interface SVGPathSegArcAbs extends SVGPathSeg {
-
-  /** @domName SVGPathSegArcAbs.angle */
-  num angle;
-
-  /** @domName SVGPathSegArcAbs.largeArcFlag */
-  bool largeArcFlag;
-
-  /** @domName SVGPathSegArcAbs.r1 */
-  num r1;
-
-  /** @domName SVGPathSegArcAbs.r2 */
-  num r2;
-
-  /** @domName SVGPathSegArcAbs.sweepFlag */
-  bool sweepFlag;
-
-  /** @domName SVGPathSegArcAbs.x */
-  num x;
-
-  /** @domName SVGPathSegArcAbs.y */
-  num y;
-}