Drop messages that slow down VC with big repositories.

Index: lisp/vc/vc.el
--- lisp/vc/vc.el.orig
+++ lisp/vc/vc.el
@@ -3689,13 +3689,11 @@ It returns the last revision that changed LINE number 
 (defun vc-file-tree-walk (dirname func &rest args)
   "Walk recursively through DIRNAME.
 Invoke FUNC f ARGS on each VC-managed file f underneath it."
-  (vc-file-tree-walk-internal (expand-file-name dirname) func args)
-  (message "Traversing directory %s...done" dirname))
+  (vc-file-tree-walk-internal (expand-file-name dirname) func args))
 
 (defun vc-file-tree-walk-internal (file func args)
   (if (not (file-directory-p file))
       (when (vc-backend file) (apply func file args))
-    (message "Traversing directory %s..." (abbreviate-file-name file))
     (let ((dir (file-name-as-directory file)))
       (mapcar
        (lambda (f) (or