Automatic Updates: Add a rollback functionality upon installation failure, the rollback package will be available for partial-updates for automatic updates and be similar to our existing partial builds (but in reverse).
A further iteration of this is to also detect whitescreens (fatals) after a auto update, and trigger the rollback for that too.
See #22704

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Automatic Updates: Disable Automatic updates for Mercurial(HG) and Bazaar(bzr) version control systems in addition to Git and SVN. Props jamescollins. See #22704

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Automatic Updates: Remove some debug from [25649] See #22704

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