LibWeb: Add NamedNodeMap::setNamedItemNS() method

This patch adds implementation of the missing `setNamedItemNS()` method.

Userland/Libraries/LibWeb/DOM/NamedNodeMap.cpp

@@ -92,6 +92,12 @@ WebIDL::ExceptionOr<Attr const*> NamedNodeMap::set_named_item(Attr& attribute)
     return set_attribute(attribute);
 }
 
+// https://dom.spec.whatwg.org/#dom-namednodemap-setnameditemns
+WebIDL::ExceptionOr<Attr const*> NamedNodeMap::set_named_item_ns(Attr& attribute)
+{
+    return set_attribute(attribute);
+}
+
 // https://dom.spec.whatwg.org/#dom-namednodemap-removenameditem
 WebIDL::ExceptionOr<Attr const*> NamedNodeMap::remove_named_item(StringView qualified_name)
 {

Userland/Libraries/LibWeb/DOM/NamedNodeMap.h

@@ -38,6 +38,7 @@ public:
     Attr const* get_named_item(StringView qualified_name) const;
     Attr const* get_named_item_ns(StringView namespace_, StringView local_name) const;
     WebIDL::ExceptionOr<Attr const*> set_named_item(Attr& attribute);
+    WebIDL::ExceptionOr<Attr const*> set_named_item_ns(Attr& attribute);
     WebIDL::ExceptionOr<Attr const*> remove_named_item(StringView qualified_name);
     WebIDL::ExceptionOr<Attr const*> remove_named_item_ns(StringView namespace_, StringView local_name);
 

Userland/Libraries/LibWeb/DOM/NamedNodeMap.idl

@@ -9,7 +9,7 @@ interface NamedNodeMap {
     Attr? getNamedItemNS(DOMString? namespace, DOMString localName);
 
     [CEReactions] Attr? setNamedItem(Attr attr);
-    // [CEReactions] Attr? setNamedItemNS(Attr attr);
+    [CEReactions] Attr? setNamedItemNS(Attr attr);
 
     [CEReactions] Attr removeNamedItem(DOMString qualifiedName);
     [CEReactions] Attr removeNamedItemNS(DOMString? namespace, DOMString localName);