[css-easing-2] linear() fixup happens at used-value time, not after parsing. #11211

Author: tabatkins

css-easing-2/Overview.bs

@@ -252,8 +252,9 @@ A [=linear easing function=] has the following syntax:
   one per <<percentage>>.
 
   If an argument lacks a <<percentage>>,
-  its [=input progress value=] is initially empty,
-  but that is immediately corrected by [=linear() canonicalization=] after parsing.
+  its [=input progress value=] is initially empty.
+  This is corrected at [=used value=] time
+  by [=linear() canonicalization=].
 
 <div algorithm>
   To <dfn export lt="linear() canonicalization|canonicalize a linear()">canonicalize a linear()</dfn> function's [=linear()/control points=],