Remove explicit interface versions of dartdoc files.

lib/html/doc/interface/Rect.dartdoc

Index: lib/html/doc/interface/Rect.dartdoc
diff --git a/lib/html/doc/interface/Rect.dartdoc b/lib/html/doc/interface/Rect.dartdoc
deleted file mode 100644
index 330f509e7e850d35e5823af96d2df39b7cee6fe4..0000000000000000000000000000000000000000
--- a/lib/html/doc/interface/Rect.dartdoc
+++ /dev/null
@@ -1,23 +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 Rect
-interface Rect {
-
-  /** @domName Rect.bottom */
-  final CSSPrimitiveValue bottom;
-
-  /** @domName Rect.left */
-  final CSSPrimitiveValue left;
-
-  /** @domName Rect.right */
-  final CSSPrimitiveValue right;
-
-  /** @domName Rect.top */
-  final CSSPrimitiveValue top;
-}