Latest commit b2767b2 Aug 13, 2016 @hazzik hazzik NH-3874 - Fix NullReferenceException
If user was trying to remove or evict a collection which key is of
IUserType when the ReturnedType property of the IUserType implementation
returns a base type of an actually persisted type (eg. object) the
MessageHelper.CollectionInfoString could throw an NullReferenceException
due to incorrect type check.