Remove explicit interface versions of dartdoc files.

lib/html/doc/interface/SVGTextPositioningElement.dartdoc

Index: lib/html/doc/interface/SVGTextPositioningElement.dartdoc
diff --git a/lib/html/doc/interface/SVGTextPositioningElement.dartdoc b/lib/html/doc/interface/SVGTextPositioningElement.dartdoc
deleted file mode 100644
index cdcf2d948667ecfd4d65ddddeaa93500e7414824..0000000000000000000000000000000000000000
--- a/lib/html/doc/interface/SVGTextPositioningElement.dartdoc
+++ /dev/null
@@ -1,26 +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 SVGTextPositioningElement
-interface SVGTextPositioningElement extends SVGTextContentElement {
-
-  /** @domName SVGTextPositioningElement.dx */
-  final SVGAnimatedLengthList dx;
-
-  /** @domName SVGTextPositioningElement.dy */
-  final SVGAnimatedLengthList dy;
-
-  /** @domName SVGTextPositioningElement.rotate */
-  final SVGAnimatedNumberList rotate;
-
-  /** @domName SVGTextPositioningElement.x */
-  final SVGAnimatedLengthList x;
-
-  /** @domName SVGTextPositioningElement.y */
-  final SVGAnimatedLengthList y;
-}