anchor.diff:    /// This should match the flag name in precache.dart
     final String name;
   
  -  /// Whether this artifact should not be usable on stable branches.
  +  /// Whether this artifact should be unavailable on stable branches.
     final bool unstable;
   
     /// Artifacts required for Android development.
  
positive.code:   /// Artifacts required for iOS development.
    static const DevelopmentArtifact iOS = DevelopmentArtifact._('ios');
  
    /// Artifacts required for web development,
    static const DevelopmentArtifact web = DevelopmentArtifact._('web', unstable: true);
  
    /// Artifacts required for desktop macOS.
  
negative.code:   /// Artifacts required for desktop Windows.
    static const DevelopmentArtifact windows = DevelopmentArtifact._('windows', unstable: true);
  
    /// Artifacts required for desktop Linux.
    static const DevelopmentArtifact linux = DevelopmentArtifact._('linux', unstable: true);
  
    /// Artifacts required for Fuchsia.
    static const DevelopmentArtifact fuchsia = DevelopmentArtifact._('fuchsia', unstable: true);
  
    /// Artifacts required by any development platform.
    static const DevelopmentArtifact universal = DevelopmentArtifact._('universal');
  
    /// The vaulues of DevelopmentArtifacts.
  