Not sure whether sort, tr or xargs returning non-zero status, but
one of them sometimes does.
Test: manually
Change-Id: I8f2b862de9d6e22dd90068252e393533ec992dfd
Empty results cause grep/egrep to return a non-zero status.
Bug: 145347092
Bug: 141258651
Bug: 69058154
Bug: 143285996
Test: manual run for notice files
Change-Id: I25d54ae307b97a07a98e99c54f283437718fe657