addremove: don't audit the path for paths already in the dirstate

Now that dirstate.walk returns None for paths under symlink directories,
addremove doesn't need to validate each path it sees to look for files
under symlinks.

On a large repository this brings addremove from 6.3 seconds down to 3.65 (42%)
since addremove no longer has to stat every directory of every file to determine
if the file is inside a symlink directory. I put it through our benchmark and
see no perf hit to any other commands.

mercurial/scmutil.py

@@ -752,17 +752,14 b' def addremove(repo, pats=[], opts={}, dr'
     ctx = repo[None]
     walkresults = repo.dirstate.walk(m, sorted(ctx.substate), True, False)
     for abs in sorted(walkresults):
-        good = audit_path.check(abs)
-
         st = walkresults[abs]
         dstate = repo.dirstate[abs]
-        if good and dstate == '?':
+        if dstate == '?' and audit_path.check(abs):
             unknown.append(abs)
             if repo.ui.verbose or not m.exact(abs):
                 rel = m.rel(abs)
                 repo.ui.status(_('adding %s\n') % ((pats and rel) or abs))
-        elif (dstate != 'r' and
-              (not good or not st or
+        elif (dstate != 'r' and (not st or
                (stat.S_ISDIR(st.st_mode) and not stat.S_ISLNK(st.st_mode)))):
             deleted.append(abs)
             if repo.ui.verbose or not m.exact(abs):