Plus refactoring of the KillAllXXXActions and tests to share
common code.
This essentially completes the KillAll []s. We can now reliably
clean out everything except for:
* Lock - harmless to leave alone or delete from the gae console
* GaeUserIdConverter - same
* RdeRevision - filed [] to track, but harmless if not cleaned up
* ForeignKeyHostIndex of renamed hosts - tracked in []
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=120781975
