setActiveGroup null, 0 length, unwritable dir should fail

with this change, VTS test needs to run in /data/system/
due to SELinux policy + Linux directory permissions

Test: run VTS tests and make sure they all pass
Fixes 37153318

Change-Id: Ib1f19ce7fc0d08ae2941aec5c08c5857c7a9f2fd
2 files changed