IdentityPromoter typedef
IdentityPromoter =
Future<IdentityPromotion> Function()
Asks the host to identify the current viewer, or to let go of that identity.
Returns why the attempt ended as it did, so a document can tell a decline from an impossibility — see PromotionOutcome. Anything but PromotionOutcome.promoted leaves the session carrying what it had.
Implementation
typedef IdentityPromoter = Future<IdentityPromotion> Function();