bug#13977: 24.3.50; buffer-file-coding-system not set correctly

[Richard Copley <rcopley@gmail.com>]

On Windows, visit a plain ASCII text file with LF line endings. The
value of `buffer-file-coding-system' is `iso-latin-1-dos' (should be
`iso-latin-1-unix'). Modify and save the file. The file now has CRLF
line endings.
This was introduced recently in the trunk.


In GNU Emacs 24.3.50.1 (i386-mingw-nt6.2.9200)
 of 2013-03-16 on MACHINE
Bzr revision: 112057 jan.h.d@swipnet.se-20130316125847-4km32l5zt9fbbxb0
Windowing system distributor `Microsoft Corp.', version 6.2.9200
Configured using:
 `configure --with-gcc (4.7) --cflags -I c:/gnuwin32/include --ldflags
 -L c:/gnuwin32/lib'

Important settings:
  value of $LANG: ENG
  locale-coding-system: cp1252
  default enable-multibyte-characters: t

Major mode: Text

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:

C-x C-f n e w . t x t <return> a <return> b <return>
c <return> C-x <return> c u n i x <return> C-x C-s
M-: ( n t h SPC 7 SPC ( f i l e - a t t r i b u t e s
SPC " n e w . t x t " ) ) <return> C-x C-v <return>
SPC <backspace> C-x C-s M-: <up> <return> M-x r e p o
r t - e m a c s - b u f <backspace> g <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
(New file)
Saving file c:/Users/Buster/new.txt...
Wrote c:/Users/Buster/new.txt
6 (#o6, #x6)
Saving file c:/Users/Buster/new.txt...
Wrote c:/Users/Buster/new.txt
9 (#o11, #x9)

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
easymenu mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums
mm-util mail-prsvr mail-utils time-date tooltip ediff-hook vc-hooks
lisp-float-type mwheel dos-w32 ls-lisp w32-common-fns disp-table w32-win
w32-vars tool-bar dnd fontset image regexp-opt fringe tabulated-list
newcomment lisp-mode register page menu-bar rfn-eshadow timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core frame cham
georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
korean japanese hebrew greek romanian slovak czech european ethiopic
indian cyrillic chinese case-table epa-hook jka-cmpr-hook help simple
abbrev minibuffer button faces cus-face macroexp files text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote make-network-process w32notify w32
multi-tty emacs)