anchor.diff:  // 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.
   
  -/// Constants for use in metadata annotations such as `@protected`.
  +/// Constants for use in metadata annotations.
   ///
   /// See also `@deprecated` and `@override` in the `dart:core` library.
   ///
  
positive.code: ///   name that does not have this annotation, or
  /// * an invocation of a method or function does not include an argument
  ///   corresponding to a named parameter that has this annotation.
  const _Required required = const _Required();
  
  class _Factory {
    const _Factory();
  
negative.code: class _Protected {
    const _Protected();
  }
  