Issue #2382239 by chx: InstallerKernel is undocumented and hardwires bootstrap config storage
Issue #2354705 by yannisc: Mark a couple of asset services as non public
Revert "Issue #2382239 by chx: InstallerKernel is undocumented and hardwires bootstrap config storage"

This reverts commit 6389cda9afbafbc773d6a4e8aa8c566f79d24919.