anchor.diff:  //  - Element 6: The enum index of the |fontStyle|.
   //
   Int32List _encodeTextStyle(Color color,
  -                           List<TextDecoration> decoration,
  +                           TextDecoration decoration,
                              Color decorationColor,
                              TextDecorationStyle decorationStyle,
                              FontWeight fontWeight,
  
positive.code: class TextStyle {
    TextStyle({
      Color color,
      List<TextDecoration> decoration,
      Color decorationColor,
      TextDecorationStyle decorationStyle,
      FontWeight fontWeight,
  
negative.code: }
  
  /// A linear decoration to draw near the text
  class TextDecoration {
    const TextDecoration._(this._mask);
  
    /// Constructs a decoration that paints the union of all the given decorations.
    factory TextDecoration.combine(List<TextDecoration> decorations) {
      int mask = 0;
      for (TextDecoration decoration in decorations)
        mask |= decoration._mask;
      return new TextDecoration._(mask);
    }
  
    final int _mask;
  
    /// Whether this decoration will paint at least as much decoration as the given decoration.
    bool contains(TextDecoration other) {
      return (_mask | other._mask) == _mask;
    }
  
    /// Do not draw a decoration
    static const TextDecoration none = const TextDecoration._(0x0);
  
    /// Draw a line underneath each line of text
    static const TextDecoration underline = const TextDecoration._(0x1);
  
    /// Draw a line above each line of text
    static const TextDecoration overline = const TextDecoration._(0x2);
  
    /// Draw a line through each line of text
    static const TextDecoration lineThrough = const TextDecoration._(0x4);
  
    bool operator ==(dynamic other) {
      if (identical(this, other))
        return true;
      if (other is! TextDecoration)
        return false;
      final TextDecoration typedOther = other;
      return _mask == typedOther._mask;
    }
  
    int get hashCode => _mask.hashCode;
  
    String toString() {
      if (_mask == 0)
        return 'TextDecoration.none';
      List<String> values = <String>[];
      if (_mask & underline._mask != 0)
        values.add('underline');
      if (_mask & overline._mask != 0)
        values.add('overline');
      if (_mask & lineThrough._mask != 0)
        values.add('lineThrough');
      if (values.length == 1)
        return 'TextDecoration.${values[0]}';
      return 'TextDecoration.combine([${values.join(", ")}])';
    }
  }
  
  /// The style in which to draw a text decoration
  