Auto merge of #20030 - emilio:useless-return-is-useless, r=nox

style: Remove useless code after #19994

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components/style/gecko/data.rs

@@ -148,14 +148,6 @@ impl PerDocumentStyleData {
     }
 }
 
-impl Drop for PerDocumentStyleDataImpl {
-    fn drop(&mut self) {
-        if !structs::GECKO_IS_NIGHTLY {
-            return
-        }
-    }
-}
-
 impl PerDocumentStyleDataImpl {
     /// Recreate the style data if the stylesheets have changed.
     pub fn flush_stylesheets<E>(