bug#3436: 23.0.91; Gnus: gnus-summary-toggle-truncation needs manual update

In Gnus summary buffer there is command gnus-summary-toggle-truncation
(C-t). It seems to do pretty much the same as toggle-truncate-lines
command, except that the former does not update the buffer after toggle.

Try this:

 1. Enter Gnus summary buffer

 2. Make the window so narrow that the lines don't fit horizontally in
    the window.

 3. Press C-t

 4. Nothing happens until you update the window, with C-l, for example.

This used to work with my Emacs 22.2.


In GNU Emacs 23.0.91.1 (i486-pc-linux-gnu, GTK+ Version 2.12.11)
 of 2009-03-21 on elegiac, modified by Debian
 (emacs-snapshot package, version 1:20090320-1~lenny1)
Windowing system distributor `The X.Org Foundation', version 11.0.10402000
configured using `configure  '--build' 'i486-linux-gnu' '--host' 'i486-linux-gnu' '--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib' '--localstatedir=/var' '--infodir=/usr/share/info' '--mandir=/usr/share/man' '--with-pop=yes' '--enable-locallisppath=/etc/emacs-snapshot:/etc/emacs:/usr/local/share/emacs/23.0.91/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/23.0.91/site-lisp:/usr/share/emacs/site-lisp' '--with-x=yes' '--with-x-toolkit=gtk' 'build_alias=i486-linux-gnu' 'host_alias=i486-linux-gnu' 'CFLAGS=-DDEBIAN -DSITELOAD_PURESIZE_EXTRA=5000 -g -O2' 'LDFLAGS=-g -Wl,--as-needed' 'CPPFLAGS=''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: en_US.UTF-8
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: fi_FI.UTF-8
  value of $XMODIFIERS: @im=none
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t

Major mode: Summary

Minor modes in effect:
  TeX-PDF-mode: t
  gnus-agent-mode: t
  shell-dirtrack-mode: t
  ergo-movement-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
  transient-mark-mode: t