bug#23814: 24.5; bug of hz coding-system

[ynyaaa@gmail.com]

hz coding-system should encode chinese-gb2312 characters,
it may fail to encode text without charset property.

current-language-environment
=>"Japanese"

;; wrong
(encode-coding-string "\x4E00" 'hz)
=>"\e$B0l~}"

;; correct
(encode-coding-string (propertize "\x4E00" 'charset 'chinese-gb2312) 'hz)
=>"~{R;~}"


When the second byte of chinese-gb2312 character equals to ?~,
hz coding-system may faile to decode.

(encode-coding-string (propertize "\x670D" 'charset 'chinese-gb2312) 'hz)
=>"~{7~~}"

;; wrong
(decode-coding-string "~{7~~}" 'hz)
=>"\300\267"



In GNU Emacs 24.5.1 (i686-pc-mingw32)
 of 2015-04-11 on LEG570
Windowing system distributor `Microsoft Corp.', version 6.0.6002
Configured using:
 `configure --prefix=/c/usr --host=i686-pc-mingw32'

Important settings:
  value of $LANG: JPN
  locale-coding-system: cp932

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  electric-indent-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 messages:

Load-path shadows:
None found.

Features:
(network-stream starttls tls mailalias smtpmail auth-source eieio
byte-opt bytecomp byte-compile cl-extra cl-loaddefs cl-lib cconv
eieio-core password-cache rect warnings china-util misearch
multi-isearch pp shadow sort gnus-util mail-extr emacsbug message
format-spec rfc822 mml 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 help-mode easymenu advice
help-fns time-date japan-util tooltip electric uniquify 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 prog-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 nadvice loaddefs 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)

Memory information:
((conses 8 94845 27098)
 (symbols 32 19573 0)
 (miscs 32 77 279)
 (strings 16 16482 13821)
 (string-bytes 1 462365)
 (vectors 8 12746)
 (vector-slots 4 519456 11240)
 (floats 8 62 556)
 (intervals 28 606 13)
 (buffers 508 18))