[scroll-animations-1] Return negative infinity for times coinciding with zero-length range. #8114

Author: fantasai

scroll-animations-1/Overview.bs

@@ -1375,9 +1375,8 @@ spec: cssom-view-1; type: dfn;
 					and return it.
 
 					If the start and end points of the [=named timeline range=] coincide,
-					return negative infinity for time values before it,
-					positive infinity for time values after it,
-					and zero for time values coinciding with that point.
+					return negative infinity for time values earlier or equal to that point,
+					and positive infinity for time values after it.
 
 				<dt>
 					If {{AnimationTimeOptions/range}} is provided