A few errors emerged when doing an integration test against the actual API. I've updated the unit tests to reflect the correct behavior.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148793856
This simplifies the tests for KmsKeyring and KmsUpdater.
This is a followup to []
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148496758