Function webext_storage::db::unurl_path

fn unurl_path(p: impl AsRef<Path>) -> PathBuf

Path is basically just a str with no validation, and so in practice it could contain a file URL. Rusqlite takes advantage of this a bit, and says AsRef<Path> but really means "anything sqlite can take as an argument".

Swift loves using file urls (the only support it has for file manipulation is through file urls), so it's handy to support them if possible.