Domains that are reserved with type NAME_COLLISION can be registered defensively
during sunrise only, but DNS can never resolve for them. Correspondingly, we
need to apply the SERVER_HOLD status for such registrations. We also send the
registrar a poll message informing them of this act.
This brings us up to feature parity with end-date sunrise (implemented in
DomainAllocateFlow), which already has all of this handling.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=205277728