Allow `otapreopt_chroot` to use a flattened Runtime APEX package.
- Allow (again) `otapreopt` (running as `postinstall_dexopt`) to
execute `dex2oat` from `/postinstall` -- this is for the case where
it is located in a flattened Runtime APEX in
`/postinstall/system/apex`.
- Allow `dex2oat` to read directories under `/postinstall`.
- Allow `otapreopt_chroot` to unmount flattened APEX packages under
`/postinstall/system/apex` (which are bind-mounted in
`/postinstall/apex`).
Test: A/B OTA update test (asit/dexoptota/self_full).
Bug: 127543974
Bug: 123684826
Bug: 113373927
Change-Id: Ie023ee5c64989ea071e1683f31073a70c93cac18
3 files changed