LibWeb: Make word-spacing and letter-spacing default value compute to 0

Author: https://github.com/tcl3
Commit: bd7348949a
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/6137
Reviewed-by: https://github.com/AtkinsSJ ✅
Reviewed-by: https://github.com/Calme1709
Reviewed-by: https://github.com/gmta ✅

Libraries/LibWeb/CSS/StyleComputer.cpp

@@ -3136,6 +3136,11 @@ NonnullRefPtr<StyleValue const> StyleComputer::compute_value_of_property(Propert
         return compute_border_or_outline_width(specified_value, get_property_specified_value(PropertyID::BorderTopStyle), computation_context);
     case PropertyID::OutlineWidth:
         return compute_border_or_outline_width(specified_value, get_property_specified_value(PropertyID::OutlineStyle), computation_context);
+    case PropertyID::LetterSpacing:
+    case PropertyID::WordSpacing:
+        if (specified_value->to_keyword() == Keyword::Normal)
+            return LengthStyleValue::create(Length::make_px(0));
+        return specified_value;
     case PropertyID::FillOpacity:
     case PropertyID::FloodOpacity:
     case PropertyID::Opacity: