It makes sense for all mapreduces to run in backend, especially onces
that are scheduled regularly to run in cron like this one now. We don't
have many instances configured for the tools service anymore on some
of our environments, so backend is the friendliest place for a mapreduce
to run.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=168882122
This pattern will mainly be used for data migrations, i.e. updating all
HistoryEntries' DomainTransactionRecords to the new schema.
TESTED=Ran in alpha, the underlying data dropped non-Objectify fields as
expected.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=168684356
