Auto merge of #19220 - CYBAI:font-variant-east-asian-out-of-mako, r=emilio

style: Move font-variant-east-asian outside of mako

This is a sub-PR of #19015
r? emilio

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #19216
- [x] These changes do not require tests

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ports/geckolib/glue.rs

@@ -186,6 +186,7 @@ pub extern "C" fn Servo_Initialize(dummy_url_data: *mut URLExtraData) {
     origin_flags::assert_flags_match();
     parser::assert_parsing_mode_match();
     traversal_flags::assert_traversal_flags_match();
+    specified::font::assert_variant_east_asian_matches();
 
     // Initialize the dummy url data
     unsafe { DUMMY_URL_DATA = dummy_url_data; }