bug#12218: 24.2.50; vc-ediff: Pressing `n' moves focus away from ediff control panel

[Jambunathan K]

My Bzr checkout is at 

    kjambunathan@debian-6:~/src/emacs/trunk/lisp$ bzr version-info
    revision-id: rgm@gnu.org-20120817072823-0zjgqf10g1d0vcf1
    date: 2012-08-17 00:28:23 -0700
    build-date: 2012-08-17 15:46:53 +0530
    revno: 109655
    branch-nick: trunk

1. C-x C-f <some modified file>
2. M-x vc-ediff
3. Press `n' in the control panel
4. Note that the one of the src buffer - buffer B specifically - becomes
   receives focus (or whatever you call it)
5. Pressing another `n' and it modifies the src buffer.  

I would expect that focus never leave the ediff control panel.

Seems like a recent regression to me.