This is more efficient (we were constructing all the
providers and the map anew for every flow) and prettier.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125479328
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