merge method
Implementation
ZeroTextfieldStyleSet merge(ZeroTextfieldStyleSet? other) {
if (other == null) return this;
return ZeroTextfieldStyleSet._(
filled: filled.merge(other.filled),
outline: outline.merge(other.outline),
rounded: rounded.merge(other.rounded),
underline: underline.merge(other.underline),
defaultDecorationType: other.defaultDecorationType,
textfieldSize: other.textfieldSize,
focusedBorderColor: other.focusedBorderColor,
focusedColor: other.focusedColor,
);
}