Emacs: adapt read-file-name invocation for (non-X)Emacs 21.4.
this patch deters hg-read-file-name from passing hg-file-history to
read-file-name as 6th parameter in non-X Emacs environment.
3210 files updated, 0 files merged, 1 files removed, 0 files unresolvedsub/b not presentsub not present