Verify files from non-installed packages again (RhBug:826589)

Verify files from non-installed packages again (RhBug:826589)

- Verifying files against the originating, non-installed package can
  be useful sometimes, eg if rpmdb is broken or cannot be trusted.
  Of course such verification will give false positives on files that
  were intentionally skipped during installation (nodocs, wrong color,
  netshared...), that can't be helped.
- This restores the former behavior that was erroneously changed
  in commit adbd484372cb38aca5aca3c6dba3b2ca9cae93d1 while "fixing"
  an unhandled enumeration in the switch. Doh.