LibWeb/IDB: Implement IDBObjectStore::keyPath

Author: https://github.com/stelar7
Commit: 594ba28c35
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/4077
Reviewed-by: https://github.com/AtkinsSJ
Reviewed-by: https://github.com/gmta ✅

Libraries/LibWeb/IndexedDB/IDBObjectStore.h

@@ -23,6 +23,8 @@ public:
     virtual ~IDBObjectStore() override;
     [[nodiscard]] static GC::Ref<IDBObjectStore> create(JS::Realm&, GC::Ref<ObjectStore>, GC::Ref<IDBTransaction>);
 
+    JS::Value key_path() const;
+
 protected:
     explicit IDBObjectStore(JS::Realm&, GC::Ref<ObjectStore>, GC::Ref<IDBTransaction>);
     virtual void initialize(JS::Realm&) override;