This color space is often used as a reference in WPT tests, having
support for it makes us pass 15 new tests:
- css/css-color/rec2020-001.html
- css/css-color/rec2020-002.html
- css/css-color/rec2020-003.html
- css/css-color/rec2020-004.html
- css/css-color/rec2020-005.html
- css/css-color/predefined-011.html
- css/css-color/predefined-012.html