This is an followup based on #1905152-41: Integrate config schema with locale, so shipped configuration is translated:
Can we piggy-back the configuration translation update on the existing second translation import wizard step / batch?
Indeed, we don't want to display three translation tasks in the installer:
This gives the translation tasks too much weight and adds to a picture that interface translation was something incredibly complex and heavyweight with Drupal. While to some extent this might be true in code, it shouldn't be in the UI.
With slight changes in the installer, we can easily queue two batches. I even made a patch, and it worked, but I'm not too happy with the results.
Because it would be a lot nicer, if we could use a single batch set with a single progress bar but separate progress messages.
Though it would just as well make a lot of sense for module_enable(), I suspect that this currently isn't possible. If that's correct, the way to go would be to refactor the Batch API allowing for more complex batch sets.