LibWeb: Add AbstractImageStyleValue::natural_aspect_ratio()

Author: https://github.com/MacDue
Commit: d2c96e213f
Pull-request: https://github.com/SerenityOS/serenity/pull/22508
Issue: https://github.com/SerenityOS/serenity/issues/20992
Reviewed-by: https://github.com/awesomekling
Reviewed-by: https://github.com/nico

Userland/Libraries/LibWeb/CSS/StyleValues/AbstractImageStyleValue.h

@@ -23,6 +23,15 @@ public:
     virtual Optional<CSSPixels> natural_width() const { return {}; }
     virtual Optional<CSSPixels> natural_height() const { return {}; }
 
+    virtual Optional<CSSPixelFraction> natural_aspect_ratio() const
+    {
+        auto width = natural_width();
+        auto height = natural_height();
+        if (width.has_value() && height.has_value())
+            return *width / *height;
+        return {};
+    }
+
     virtual void load_any_resources(DOM::Document&) {};
     virtual void resolve_for_size(Layout::NodeWithStyleAndBoxModelMetrics const&, CSSPixelSize) const {};