Reland "Change to using sysprop for services.core.unboosted"

This reverts commit 123fba9ffb3c5d2755006cc6b7d480b1a1b01162.

Reason for revert: Fix build error (ag/11388833)

Bug: 124531214
Change-Id: If4810b59ba0665b7fec1329982800674297d891c
2 files changed