Function to_ask 

fn to_ask(
    own: &str,
    own_entry: &Entry,
    entries: &[Entry],
    answered: &[String],
    forgotten: &dyn Fn(&str) -> bool,
    quiet_since: &dyn Fn(&str) -> Option<i64>,
    now: i64,
) -> Option<Entry>

Of the other phones in the folder, the one to ask about, if any: on a phone sharing, one that has not stopped sharing, nor said anything for ASK_AFTER as this device sees it (quiet_since: the later of when this device saw its entry change and its own last word; none known: not asked), nor been asked about (Asked), nor been replaced or forgotten here; the one heard of last.