anchor.diff:    /// should, if possible, use to render their user interface.
     ///
     /// The [onLocaleChanged] callback is called whenever this value changes.
  +  ///
  +  /// See also:
  +  ///
  +  ///  * [WidgetsBindingObserver], for a mechanism at the widgets layer to
  +  ///    observe when this value changes.
     Locale get locale => _locale;
     Locale _locale;
   
     /// A callback that is invoked whenever [locale] changes value.
  +  ///
  +  /// See also:
  +  ///
  +  ///  * [WidgetsBindingObserver], for a mechanism at the widgets layer to
  +  ///    observe when this callback is invoked.
     VoidCallback onLocaleChanged;
   
     /// A callback that is invoked to notify the application that it is an
  
positive.code: ///
  /// For a generic class that represents distances around a rectangle, see the
  /// [EdgeInsets] class.
  class WindowPadding {
    const WindowPadding._({ this.left, this.top, this.right, this.bottom });
  
  
negative.code:   /// The [onDrawFrame] callback is invoked immediately after [onBeginFrame],
    /// after draining any microtasks (e.g. completions of any [Future]s) queued
    /// by the [onBeginFrame] handler.
    ///
    /// See also:
    ///
    ///  * [SchedulerBinding], the Flutter framework class which manages the
    ///    scheduling of frames.
    ///  * [RendererBinding], the Flutter framework class which manages layout and
    ///    painting.
    FrameCallback onBeginFrame;
  
    /// A callback that is invoked for each frame after [onBeginFrame] has
    /// completed and after the microtask queue has been drained. This can be
    /// used to implement a second phase of frame rendering that happens
    /// after any deferred work queued by the [onBeginFrame] phase.
    ///
    /// See also:
    ///
    ///  * [SchedulerBinding], the Flutter framework class which manages the
    ///    scheduling of frames.
    ///  * [RendererBinding], the Flutter framework class which manages layout and
    ///    painting.
    VoidCallback onDrawFrame;
  
    /// A callback that is invoked when pointer data is available.
    ///
    /// See also:
    ///
    ///  * [GestureBinding], the Flutter framework class which manages pointer
    ///    events.
    PointerDataPacketCallback onPointerDataPacket;
  
    /// The route or path that the operating system requested when the application
  