servo: Merge #19689 - Fix typo. san-serif -> sans-serif (from pyfisch:san-serif); r=jdm

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Source-Repo: https://github.com/servo/servo
Source-Revision: 782e3fe4e47b4be47bf8ec87e6ef566881c312b0

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : ba9aa56e5a5435735368ffa50738785c43e9d672

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

@@ -203,7 +203,7 @@ impl FontList {
     // Only used in the unlikely case where no font xml mapping files are found.
     fn fallback_font_families() -> Vec<FontFamily> {
         let alternatives = [
-            ("san-serif", "Roboto-Regular.ttf"),
+            ("sans-serif", "Roboto-Regular.ttf"),
             ("Droid Sans", "DroidSans.ttf"),
         ];