enable text-overflow property for Servo

Signed-off-by: Richard Tjokroutomo <[email protected]>
Co-authored-by: Oriol Brufau <[email protected]>

Author: RichardTjokroutomo

style/properties/longhands/text.mako.rs

@@ -9,7 +9,6 @@ ${helpers.predefined_type(
     "TextOverflow",
     "computed::TextOverflow::get_initial_value()",
     engines="gecko servo",
-    servo_pref="layout.unimplemented",
     animation_type="discrete",
     boxed=True,
     spec="https://drafts.csswg.org/css-ui/#propdef-text-overflow",

style/values/specified/text.rs

@@ -182,7 +182,7 @@ impl Parse for InitialLetter {
     ToResolvedValue,
     ToShmem,
 )]
-#[repr(C, u8)]
+#[repr(C)]
 pub enum TextOverflowSide {
     /// Clip inline content.
     Clip,
@@ -228,21 +228,23 @@ impl Parse for TextOverflow {
         input: &mut Parser<'i, 't>,
     ) -> Result<TextOverflow, ParseError<'i>> {
         let first = TextOverflowSide::parse(context, input)?;
-        Ok(
-            if let Ok(second) = input.try_parse(|input| TextOverflowSide::parse(context, input)) {
-                Self {
-                    first,
-                    second,
-                    sides_are_logical: false,
-                }
-            } else {
-                Self {
-                    first: TextOverflowSide::Clip,
-                    second: first,
-                    sides_are_logical: true,
-                }
-            },
-        )
+        #[cfg(feature = "servo")]
+        if matches!(first, TextOverflowSide::String(_)) {
+            return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError));
+        }
+        #[cfg(feature = "gecko")]
+        if let Ok(second) = input.try_parse(|input| TextOverflowSide::parse(context, input)) {
+            return Ok(Self {
+                first,
+                second,
+                sides_are_logical: false,
+            });
+        }
+        Ok(Self {
+            first: TextOverflowSide::Clip,
+            second: first,
+            sides_are_logical: true,
+        })
     }
 }