When we run ContactCreateJob, the UID of a contact is not yet known.
We can only add a photo only after we receive a reply from main create job.
Also, since we also don't want the following race condition to trigger:
- Contact1 create request
- Contact1 reply, Photo1 change request, Contact2 create request
- Contact2 reply, Photo2 change request
- Photo1 reply (here both currentContact and lastContact is Contact2)
- Photo2 reply
we only go for next contact after the previous has been fully procesed:
- Contact1 create request
- Contact1 reply, Photo1 change request
- Photo1 reply, Contact2 create request
- Contact2 reply, Photo2 change request
- Photo2 reply