servo: Merge #19642 - cleanup no need cfg target_os (from tigercosmos:c1); r=emilio

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Already in macos, no need cfg target_os

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

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Source-Repo: https://github.com/servo/servo
Source-Revision: d49cb8a47812c0e8ae25643e5437e212f5cbee16

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : b8fbbea34c7660db93f1de9b6220c57e55cf336f

servo/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";
-