Auto merge of #19642 - tigercosmos:c1, r=emilio

cleanup no need cfg target_os

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Already in macos, no need cfg target_os

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components/gfx/platform/macos/font_list.rs

@@ -42,6 +42,4 @@ pub fn last_resort_font_families() -> Vec<String> {
     vec!("Arial Unicode MS".to_owned(), "Arial".to_owned())
 }
 
-#[cfg(target_os = "macos")]
 pub static SANS_SERIF_FONT_FAMILY: &'static str = "Helvetica";
-