bug#15322: VC log buffer scrolls itself

[Glenn Morris]

I'm going to guess that this happens with svn, and that the revision you
end up on is the working revision of whatever file happens to be listed
last in the output of: svn status -v /path/to/svn/directory

Looks like a bug in vc-svn-parse-status when called with filename ==
directory, caused by the "don't trust the output's filename unless we
have to" part.