[css-values-3][css-values-4] Clarify that specs can override the default out-of-range numbers are invalid handling. Fixes #3270

Author: fantasai

css-values-3/Overview.bs

@@ -667,6 +667,7 @@ Numeric Data Types
 
 		Properties may restrict numeric values to some range.
 		If the value is outside the allowed range,
+		unless otherwise specified,
 		the declaration is invalid and must be ignored.
 
 		CSS theoretically supports infinite precision and infinite ranges for all value types;
@@ -2159,6 +2160,15 @@ Changes
 		Defined <<'property'>> syntax to refer to the property without any top-level #-multiplier,
 			to make the notation usable with common list-valued property patterns.
 			(Issue 3146)
+		Clarified that numeric values outside the allowed range
+			are not ignored if a more specific spec defines other handling.
+			(Issue 3270)
+			
+				Properties may restrict numeric values to some range.
+				If the value is outside the allowed range,
+				unless otherwise specified,
+				the declaration is invalid and must be ignored.
+			
 	
 
 	Changes since the 29 September 2016 Candidate Recommendation are:

css-values-4/Overview.bs

@@ -784,6 +784,7 @@ Numeric Data Types
 
 		Properties may restrict numeric values to some range.
 		If the value is outside the allowed range,
+		unless otherwise specified,
 		the declaration is invalid and must be ignored.
 
 		CSS theoretically supports infinite precision and infinite ranges for all value types;