[ale] Die on unexpected calls/casts/infos.

Change-Id: I8c59edac355f0122223645d37335066e611fbd42
Reviewed-on: http://review.couchbase.org/37743
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>