Followup to [] Mocking shouldn't be used when you can use the real
implementation just as easily (and more robustly) - in particular, you almost
never want to mock a value type.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=132586826
This change refactors EppMetrics from the mutable self-exporting thing that it
was into a real value type EppMetric, and delegates exporting functionality to the
BigQueryMetricsEnqueuer.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=132387660
Daggerizes all of the EPP flows. This does not change anything yet
about the flows themselves, just how they are invoked, but after
this CL it's safe to @Inject things into flow classes.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125382478