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

This reverts commit dc217b9d20d6e85d84aa8107a6bdef8ef2e05aa5.

Reason for revert:

https://android-build.googleplex.com/builds/submitted/6448376/apps/latest/view/logs/build_error.log

Change-Id: I77fb257c216093c99b27484c2e3ac6da88c34d15
2 files changed