[STOPSHIP] PackageManager: Add package setting flag for N upgrade

First upgrade to N level needs to compile apps with the first-boot
reason, as profiles are missing. The SDK level check does not work
for the preview, as the version is not incremented, yet.

Add a flag to the package settings to track the status.

Note: STOPSHIP, this will be reverted before release.

Bug: 27689078
Bug: 27872764
Change-Id: Ifd460d5235348f041ef64c9b61068af47113ddcb