anchor.diff:    /// `color` must therefore only have two entries).
     ///
     /// The behavior before `from` and after `to` is described by the `tileMode`
  -  /// argument.
  +  /// argument. For details, see the [TileMode] enum.
  +  ///
  +  /// ![](https://flutter.github.io/assets-for-api-docs/dart-ui/tile_mode_clamp_linear.png)
  +  /// ![](https://flutter.github.io/assets-for-api-docs/dart-ui/tile_mode_mirror_linear.png)
  +  /// ![](https://flutter.github.io/assets-for-api-docs/dart-ui/tile_mode_repeated_linear.png)
     ///
     /// If `from`, `to`, `colors`, or `tileMode` are null, or if `colors` or
     /// `colorStops` contain null values, this constructor will throw a
  
positive.code:   /// `color` must therefore only have two entries).
    ///
    /// The behavior before and after the radius is described by the `tileMode`
    /// argument.
    ///
    /// If `center`, `radius`, `colors`, or `tileMode` are null, or if `colors` or
    /// `colorStops` contain null values, this constructor will throw a
    /// [NoSuchMethodError].
    Gradient.radial(Offset center,
                    double radius,
                    List<Color> colors,
                    [List<double> colorStops = null,
                    TileMode tileMode = TileMode.clamp]) {
      _validateColorStops(colors, colorStops);
      final Int32List colorsBuffer = _encodeColorList(colors);
      final Float32List colorStopsBuffer = colorStops == null ? null : new Float32List.fromList(colorStops);
  
negative.code:     Offset to,
      List<Color> colors, [
      List<double> colorStops = null,
      TileMode tileMode = TileMode.clamp,
    ]) {
      _validateColorStops(colors, colorStops);
      final Float32List endPointsBuffer = _encodeTwoPoints(from, to);
  