Generate fallback permission state if it is missing.

This can happen after rollback if a package is installed after
snapshot is taken for APEX update. We need to generate reasonable
states for these packages or they may become unusable due to missing
whitelisting or permission review.

Bug: 136503238
Test: presubmit and ag/10203950 when it's ready
Change-Id: Iafe71de1f2bfff2c624f96259e28605aec84fbda