log: follow filenames through renames (issue647) In commands.log a displayer was initialized from cmdutil.show_changeset() with the initial matchfn (which designates the specified files which only is correct in the highest revision in the range). prep() is handed the correct list of files, but displayer.show() didn't use that list but keept using the original matchfn. The matchfn argument to cmdutil.show_changeset() wasn't specified in other places and is only used in .show(), so now we give the matchfn as an optional parameter to .show(). We do however still have to detect --patch and --stat from opts in show_changeset() and let it imply a matchall, but that can now be overruled with the new .show() matchfn parameter.

adding foo
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
adding foo
created new head
   rev    offset  length   base linkrev nodeid       p1           p2
     0         0       0      0       0 b80de5d13875 000000000000 000000000000
     1         0      24      0       1 0376abec49b8 000000000000 000000000000