How path property is added to V8 File Object (C++)


I am working on an old project directly built on top of CEF. I need to get the full file path when a file is open by or by file-dropping. I hope to ask the dev team, how Electron implement the feature, adding a “path” property to File Object. Tried dig into Electron source code, but get lost.

Sorry, this is may be off-topic but I . Please help, any hint is welcome. Thanks in advance.