We should be able to remove the dependency on the App Engine [] library from the frontend service, since no []s actually run there. In order to do this, we need to remove the various []-reliant classes from the frontend service build. This CL begins the process by moving the two async "flows" to a different package which is not included in the frontend service.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=142159568
669c3dc975