Restored parse-time clamping of HSL negative saturation to 0, which is current interop behavior from CSS Color 3. #9222

Author: svgeesus

css-color-4/Overview.bs

@@ -2265,6 +2265,9 @@ Converting HSL Colors to sRGB</h3>
 	representing the red, green, and blue channels of the colors,
 	normalized to the range [0, 1].
 
+	This code assumes that <em>parse-time</em> clamping
+	of negative saturation has already been applied.
+
 	<pre class="include-code lang-javascript">
 		path: hslToRgb.js
 		highlight: js