bug#2919: 23.0.91; diff-mode redefines M-q to some harmfull command

Hi,

Emacs's diff-mode redefines M-q, which I normally use for
fill-paragraph (the standard binding), since:

  revision 1.54
  date: 2004-02-02 22:08:37 +0100;  author: uid69204;  state: Exp;  lines: +2 -1;
  Bind q to `quit-window'.

I often use diff-mode to edit patches, (created by Git with git
send-email --anotate) and add comments to them before I send them by
email, and therefore fill my paragraphs (like in any other emails).
Having M-q rebound to quit-window there is harmfull. It should
definitely not be the default.

This is especially frustrating since the code says:

(easy-mmode-defmap diff-mode-shared-map
    [...]
    ;; Standard M-a is useful, so don't change M-A.
    ;;("A" . diff-ediff-patch)
    ;; Standard M-r is useful, so don't change M-r or M-R.
    ;;("r" . diff-restrict-view)
    ;;("R" . diff-reverse-direction)
    ("q" . quit-window))

so, some care has been taken not to override M-A, M-r and M-R, but M-q
still is.

Thanks,

In GNU Emacs 23.0.91.2 (i686-pc-linux-gnu, GTK+ Version 2.8.20)
 of 2009-03-17 on bauges
Windowing system distributor `The X.Org Foundation', version 11.0.70101000
configured using `configure  '--prefix=/home/moy/local/usr/''

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

Major mode: Emacs-Lisp

Minor modes in effect:
  auto-fill-function: do-auto-fill
  erc-list-mode: t
  erc-menu-mode: t
  erc-autojoin-mode: t
  erc-ring-mode: t
  erc-networks-mode: t
  erc-pcomplete-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-netsplit-mode: t
  shell-dirtrack-mode: t
  diff-auto-refine-mode: t
  erc-track-mode: t
  erc-track-minor-mode: t
  erc-match-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
  erc-readonly-mode: t
  recentf-mode: t
  global-whitespace-mode: t
  global-hl-line-mode: t
  icomplete-mode: t
  auto-image-file-mode: t
  which-function-mode: t
  show-paren-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t

Recent input:
a t c h <return> C-x k <return> C-x b . p a t c h <return> 
M-x f o M-p <backspace> <backspace> f i l l C-k - r 
e <backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> f i l l <tab> r e <tab> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
p a r <tab> <return> C-_ C-n C-e C-a C-p <return> M-x 
<up> <return> <backspace> C-n C-n C-e <left> : : C-e 
SPC <backspace> <backspace> SPC a n d SPC b e f o r 
e SPC + . C-x C-s C-x # <f11> <return> C-l <backspace> 
<C-tab> C-x b s c r a <return> M-> <S-insert> M-y M-y 
M-y C-a C-k C-_ <C-tab> C-y <backspace> <backspace> 
<S-insert> <C-tab> C-x b A r <return> C-x o <return> 
y <return> <C-f7> g s n n n <return> <return> q g s 
<f11> <C-f7> g <return> <return> <return> <return> 
<return> <return> <return> <return> <return> <return> 
<return> <return> <return> <return> <return> <return> 
<return> <return> q g s p <return> c s <f11> C-x C-f 
/ t m p / f o o . t <backspace> p a t c h <return> 
M-q C-x b . p a t c h C-s <return> C-h k M-q C-x o 
C-n <C-tab> C-h m <C-tab> C-s m - q <prior> C-h v d 
i f f - m o <tab> m a <tab> <return> <C-tab> <C-tab> 
C-n C-p C-e <left> <left> <left> <left> <return> C-s 
M - q C-s C-s C-p M-< C-s q u i t - w i n d o w C-x 
1 M-x v c - m o <tab> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> a n n <tab> <return> C-s C-s C-s C-s C-s 
C-p M-x r e p o r <tab> b u <tab> <return>

Recent messages:
Saving file /home/moy/.newsrc.eld...
Wrote /home/moy/.newsrc.eld
Saving /home/moy/.newsrc.eld...done
(New file)
Type C-x 4 C-o RET to restore the other window.
Mark saved where search started
uncompressing diff-mode.el.gz...done
Mark saved where search started
Mark set
Mark saved where search started
vc-ensure-vc-buffer: File /net/bauges/local/moy/usr/share/emacs/23.0.91/lisp/diff-mode.el.gz is not under version control
-- 
Matthieu