bug#6803: 24.0.50; pc-selection-mode no longer plays nice with dired (or vice versa)

[Tim Van Holder <tim.vanholder@gmail.com>]

Dired normally has the up and down arrows bound to dired-previous-line
(also bound to [p]) and dired-next-line (also bound to [n]), respectively.
However, when pc-selection-mode is enabled, these bindings are
apparently overridden now, to previous-line-nomark and next-line-nomark,
respectively, breaking the normal dired navigation (point is not
automatically put on the file name).
Looking at 'C-h m' for dired in an older emacs version (a 23.0.60.1
build) and today's bzr head, the cause seems to be that while the older
dired explicitly bound <up> and <down>, the current dired seems to rely
on remapping <next-line> and <previous-line> instead.

In GNU Emacs 24.0.50.10 (i686-pc-linux-gnu, GTK+ Version 2.8.20)
 of 2010-08-05 on leeloo
Windowing system distributor `The Cygwin/X Project', version 11.0.10503000
configured using `configure  '--with-x''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t