Bug 1951780: Allow parsing anchor-size function in math function in margin properties. r=firefox-style-system-reviewers,emilio

Differential Revision: https://phabricator.services.mozilla.com/D240381

servo/components/style/values/specified/length.rs

@@ -1747,6 +1747,23 @@ impl LengthPercentage {
         )
     }
 
+    /// Parses allowing the unitless length quirk, as well as allowing
+    /// anchor-positioning related function, `anchor-size()`.
+    #[inline]
+    fn parse_quirky_with_anchor_size_function<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+        allow_quirks: AllowQuirks,
+    ) -> Result<Self, ParseError<'i>> {
+        Self::parse_internal(
+            context,
+            input,
+            AllowedNumericType::All,
+            allow_quirks,
+            AllowAnchorPositioningFunctions::AllowAnchorSize,
+        )
+    }
+
     /// Parses allowing the unitless length quirk, as well as allowing
     /// anchor-positioning related functions, `anchor()` and `anchor-size()`.
     #[inline]
@@ -2140,8 +2157,9 @@ impl Margin {
         input: &mut Parser<'i, 't>,
         allow_quirks: AllowQuirks,
     ) -> Result<Self, ParseError<'i>> {
-        if let Ok(l) = input.try_parse(|i| LengthPercentage::parse_quirky(context, i, allow_quirks))
-        {
+        if let Ok(l) = input.try_parse(|i| {
+            LengthPercentage::parse_quirky_with_anchor_size_function(context, i, allow_quirks)
+        }) {
             return Ok(Self::LengthPercentage(l));
         }
         if input.try_parse(|i| i.expect_ident_matching("auto")).is_ok() {