anchor.diff:    TabBar({
       Key key,
       this.labels,
  -    this.isScrollable: false
  +    this.isScrollable: false,
  +    this.indicatorColor,
  +    this.labelColor
     }) : super(key: key, scrollDirection: Axis.horizontal);
   
     /// The labels to display in the tabs.
  
positive.code:   /// and the entire [TabBar] is scrollable. Otherwise each tab gets an equal
    /// share of the available space.
    final bool isScrollable;
  
    double get minimumHeight {
      for (TabLabel label in labels.values) {
  
negative.code: 
      ThemeData themeData = Theme.of(context);
      Color backgroundColor = Material.of(context).color;
      Color indicatorColor = config.indicatorColor ?? themeData.indicatorColor;
      if (indicatorColor == backgroundColor) {
        // ThemeData tries to avoid this by having indicatorColor avoid being the
        // primaryColor. However, it's possible that the tab bar is on a
  