LibWeb: Take namespace into account when matching attribute

Author: https://github.com/netanel-haber 🔰
Commit: d743fcb376
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2613
Reviewed-by: https://github.com/AtkinsSJ ✅

Libraries/LibWeb/DOM/NamedNodeMap.h

@@ -53,6 +53,8 @@ public:
     Attr const* remove_attribute(FlyString const& qualified_name);
     Attr const* remove_attribute_ns(Optional<FlyString> const& namespace_, FlyString const& local_name);
 
+    Attr const* get_attribute_namespace_agnostic(FlyString const& local_name) const;
+
     WebIDL::ExceptionOr<GC::Ref<Attr>> remove_attribute_node(GC::Ref<Attr>);
 
 private: