Add a way to obtain oneself

[tomayac]

Some operating systems like, for example, iOS let the user determine a special contact that should be used as "my info" for the purpose of autofill. It would be useful for the Contact Picker API to give this "myself" contact entry a special treatment (maybe as a property navigator.contacts.self or as a function navigator.contacts.getSelf(properties, options)).

(via @samthor's blog post.)