tests: skip filelog damage tests when not using revlogs
Differential Revision: https://phab.mercurial-scm.org/D3042
Set up $ hg init repo $ cd repoTry to import an empty patch $ hg import --no-commit - <<EOF > EOF applying patch from stdin abort: stdin: no diffs found [255]No dirstate backups are left behind $ ls .hg/dirstate* | sort .hg/dirstate