Remove explicit interface versions of dartdoc files.

lib/html/doc/interface/IDBKeyRange.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 IDBKeyRange
-interface IDBKeyRange default _IDBKeyRangeFactoryProvider {
-
-  /**
-   * @domName IDBKeyRange.only
-   */
-  IDBKeyRange.only(/*IDBKey*/ value);
-
-  /**
-   * @domName IDBKeyRange.lowerBound
-   */
-  IDBKeyRange.lowerBound(/*IDBKey*/ bound, [bool open]);
-
-  /**
-   * @domName IDBKeyRange.upperBound
-   */
-  IDBKeyRange.upperBound(/*IDBKey*/ bound, [bool open]);
-
-  /**
-   * @domName IDBKeyRange.bound
-   */
-  IDBKeyRange.bound(/*IDBKey*/ lower, /*IDBKey*/ upper,
-                    [bool lowerOpen, bool upperOpen]);
-
-
-  /** @domName IDBKeyRange.lower */
-  final Dynamic lower;
-
-  /** @domName IDBKeyRange.lowerOpen */
-  final bool lowerOpen;
-
-  /** @domName IDBKeyRange.upper */
-  final Dynamic upper;
-
-  /** @domName IDBKeyRange.upperOpen */
-  final bool upperOpen;
-}