Delete ChromeOS code

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1926163002

Review-Url: https://codereview.chromium.org/1926163002
diff --git a/gyp/sfntly.gyp b/gyp/sfntly.gyp
index 4e3ca5f..b23a7db 100644
--- a/gyp/sfntly.gyp
+++ b/gyp/sfntly.gyp
@@ -44,7 +44,7 @@
             },
           }
         ],
-        [ 'skia_os in ["linux", "freebsd", "openbsd", "solaris", "chromeos"]',
+        [ 'skia_os in ["linux", "freebsd", "openbsd", "solaris"]',
           { 'link_settings': { 'libraries': [ '-lpthread', ], }, },
         ],
       ],