This also deletes associated entities including indexes and history entries.
This needs to run as a prerequisite to [] which deletes all domain
application code entirely. The entities themselves need to be deleted first so
that loading DomainBases in the future doesn't accidentally get applications
which the code no longer knows how to handle.
This deletion is safe to perform because the only remaining applications in our
system are historical and we no longer refer to them. Backups will be retained
in BigQuery.
This mapreduce will be deleted at the same time that the DomainApplication code
is.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=227738528
