fonts: Merge multiple methods into PlatformFont::descriptor() (#32115)

This combines `style()`, `boldness()`, `stretchiness()` into a
`descriptor()` method which is used when creating `FontTemplate`s for
web fonts. Eventually this method will simply read font tables using
skrifa. This is the first step.

In addition, `family_name()` and `face_name()` are removed. They were
only used for debugging and the `FontIdentifier` serves for that. On
Windows, this was adding another way in which font loading could fail,
without buying us very much. The path or URL to the font is more
important when debugging than the names in the font tables.

Closes #15103.

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components/gfx/platform/macos/font.rs

@@ -26,6 +26,7 @@ use crate::font::{
     FractionalPixel, PlatformFontMethods, GPOS, GSUB, KERN,
 };
 use crate::font_cache_thread::FontIdentifier;
+use crate::font_template::FontTemplateDescriptor;
 use crate::text::glyph::GlyphId;
 
 const KERN_PAIR_LEN: usize = 6;
@@ -187,24 +188,13 @@ impl PlatformFontMethods for PlatformFont {
         Ok(handle)
     }
 
-    fn family_name(&self) -> Option<String> {
-        Some(self.ctfont.family_name())
-    }
-
-    fn face_name(&self) -> Option<String> {
-        Some(self.ctfont.face_name())
-    }
-
-    fn style(&self) -> FontStyle {
-        self.ctfont.all_traits().style()
-    }
-
-    fn boldness(&self) -> FontWeight {
-        self.ctfont.all_traits().weight()
-    }
-
-    fn stretchiness(&self) -> FontStretch {
-        self.ctfont.all_traits().stretch()
+    fn descriptor(&self) -> FontTemplateDescriptor {
+        let traits = self.ctfont.all_traits();
+        FontTemplateDescriptor {
+            weight: traits.weight(),
+            stretch: traits.stretch(),
+            style: traits.style(),
+        }
     }
 
     fn glyph_index(&self, codepoint: char) -> Option<GlyphId> {