recipient [nfc]: Throw an error explicitly on unexpected message type.
recipient [nfc]: Throw an error explicitly on unexpected message type.

This function would already go horribly wrong if passed a stream
message (which our existing code never does).  Check explicitly
up front instead.

vishwesh3/zulip-mobile,vishwesh3/zulip-mobile,vishwesh3/zulip-mobile,vishwesh3/zulip-mobile