LibWeb/IDB: Implement store_a_record_into_an_object_store

Author: https://github.com/stelar7
Commit: https://github.com/LadybirdBrowser/ladybird/commit/fb17dae42ba
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/4317
Reviewed-by: https://github.com/ADKaster ✅
Reviewed-by: https://github.com/kennethmyhra ✅

Libraries/LibWeb/IndexedDB/Internal/Index.cpp

@@ -48,4 +48,13 @@ void Index::set_name(String name)
     m_name = move(name);
 }
 
+bool Index::has_record_with_key(GC::Ref<Key> key)
+{
+    auto index = m_records.find_if([&key](auto const& record) {
+        return record.key == key;
+    });
+
+    return index != m_records.end();
+}
+
 }