Auto merge of #12689 - heycam:warning-fix, r=Ms2ger

Fix unused variable warning.

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- [ ] These changes fix #__ (github issue number if applicable).

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components/style/values/specified/mod.rs

@@ -1239,7 +1239,7 @@ pub struct UrlExtraData {
 
 impl UrlExtraData {
     #[cfg(feature = "servo")]
-    pub fn make_from(content: &ParserContext) -> Option<UrlExtraData> {
+    pub fn make_from(_context: &ParserContext) -> Option<UrlExtraData> {
         Some(UrlExtraData { })
     }