highContrast method
Implementation
RgbColour highContrast(List<RgbColour> suggestions)
{
List<RgbColour> suggestionsList = new List.from(suggestions);
if (suggestionsList.length == 0) {
throw new IllegalArgumentException("No color suggestions in list.");
}
suggestionsList.sort( new _RgbColourContrastComparator(this).compare );
return suggestionsList[0];
}