Jbuilder defines Jbuilder#call(object, *attributes) as its core API for
extracting attributes. Using `json.call do ... end` collided with that
signature and raised "wrong number of arguments (given 0, expected 1+)".
Use `json.set! :call, message.call.push_event_data` instead — also
deduplicates the field list between the jbuilder and Message#push_event_data
(both now go through Call#push_event_data).
Muhsin
02f1fdf3b6