merge method
Implementation
PillButtonBarThemeData merge(PillButtonBarThemeData? other) {
if (other == null) return this;
return PillButtonBarThemeData(
backgroundColor: other.backgroundColor ?? backgroundColor,
selectedColor: other.selectedColor ?? selectedColor,
unselectedColor: other.unselectedColor ?? unselectedColor,
selectedTextStyle: other.selectedTextStyle ?? selectedTextStyle,
unselectedTextStyle: other.unselectedTextStyle ?? unselectedTextStyle,
);
}