servo: Merge #18923 - clean up cjk for os (from tigercosmos:master); r=jdm

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r? @jdm

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #18922 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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Source-Repo: https://github.com/servo/servo
Source-Revision: 11413ab013d0d2c894fedf3c55d70d155f7fac87

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : efe3ae4d93c3dcf01cf37c7afdb9cd9801265706

servo/components/gfx/platform/freetype/font_list.rs

@@ -132,7 +132,6 @@ pub fn system_default_family(generic_name: &str) -> Option<String> {
     }
 }
 
-#[cfg(target_os = "linux")]
 pub fn last_resort_font_families() -> Vec<String> {
     vec!(
         "Fira Sans".to_owned(),
@@ -141,16 +140,4 @@ pub fn last_resort_font_families() -> Vec<String> {
     )
 }
 
-#[cfg(target_os = "windows")]
-pub fn last_resort_font_families() -> Vec<String> {
-    vec!(
-        "Arial".to_owned()
-    )
-}
-
-#[cfg(target_os = "linux")]
 pub static SANS_SERIF_FONT_FAMILY: &'static str = "DejaVu Sans";
-
-#[cfg(target_os = "windows")]
-pub static SANS_SERIF_FONT_FAMILY: &'static str = "Arial";
-