Remove explicit interface versions of dartdoc files.

lib/html/doc/interface/History.dartdoc

Index: lib/html/doc/interface/History.dartdoc
diff --git a/lib/html/doc/interface/History.dartdoc b/lib/html/doc/interface/History.dartdoc
deleted file mode 100644
index cbb6d3d04e9b99642d4b0ffd248746f47e069918..0000000000000000000000000000000000000000
--- a/lib/html/doc/interface/History.dartdoc
+++ /dev/null
@@ -1,32 +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 History
-interface History {
-
-  /** @domName History.length */
-  final int length;
-
-  /** @domName History.state */
-  final Dynamic state;
-
-  /** @domName History.back */
-  void back();
-
-  /** @domName History.forward */
-  void forward();
-
-  /** @domName History.go */
-  void go(int distance);
-
-  /** @domName History.pushState */
-  void pushState(Object data, String title, [String url]);
-
-  /** @domName History.replaceState */
-  void replaceState(Object data, String title, [String url]);
-}