Auto merge of #18241 - canaltinova:font-feature-values-lookup, r=emilio,xidorn

stylo: Implement font feature values lookup

This PR reviewed by emilio and xidorn on bugzilla. That is backed out because of Windows build problems. Fixed and landing it again.

---
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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 [Bug 1355721](https://bugzilla.mozilla.org/show_bug.cgi?id=1355721)

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components/style/properties/gecko.mako.rs

@@ -2513,8 +2513,12 @@ fn static_assert() {
 
     <% impl_simple_type_with_conversion("font_language_override", "mFont.languageOverride") %>
 
-    pub fn set_font_variant_alternates(&mut self, v: longhands::font_variant_alternates::computed_value::T) {
+    pub fn set_font_variant_alternates(&mut self,
+                                       v: longhands::font_variant_alternates::computed_value::T,
+                                       device: &Device) {
         use gecko_bindings::bindings::{Gecko_ClearAlternateValues, Gecko_AppendAlternateValues};
+        use gecko_bindings::bindings::Gecko_nsFont_ResetFontFeatureValuesLookup;
+        use gecko_bindings::bindings::Gecko_nsFont_SetFontFeatureValuesLookup;
         % for value in "normal swash stylistic ornaments annotation styleset character_variant historical".split():
             use gecko_bindings::structs::NS_FONT_VARIANT_ALTERNATES_${value.upper()};
         % endfor
@@ -2526,6 +2530,8 @@ fn static_assert() {
 
         if v.0.is_empty() {
             self.gecko.mFont.variantAlternates = NS_FONT_VARIANT_ALTERNATES_NORMAL as u16;
+            unsafe { Gecko_nsFont_ResetFontFeatureValuesLookup(&mut self.gecko.mFont); }
+            return;
         }
 
         for val in v.0.iter() {
@@ -2557,6 +2563,10 @@ fn static_assert() {
                 }
             }
         }
+
+        unsafe {
+            Gecko_nsFont_SetFontFeatureValuesLookup(&mut self.gecko.mFont, device.pres_context());
+        }
     }
 
     #[allow(non_snake_case)]

components/style/properties/properties.mako.rs

@@ -2730,12 +2730,13 @@ impl<'a> StyleBuilder<'a> {
         &mut self,
         value: longhands::${property.ident}::computed_value::T
     ) {
+        <% props_need_device = ["content", "list_style_type", "font_variant_alternates"] %>
         self.${property.style_struct.ident}.mutate()
             .set_${property.ident}(
                 value,
                 % if property.logical:
                 self.writing_mode,
-                % elif product == "gecko" and property.ident in ["content", "list_style_type"]:
+                % elif product == "gecko" and property.ident in props_need_device:
                 self.device,
                 % endif
             );