bug#21471: 25.0.50; REGRESSION: bug report with text from Info has spurious escape chars

[Drew Adams <drew.adams@oracle.com>]

Dunno whether this regression is perhaps limited to MS Windows or
mail client Outlook.  I am using both.

emacs -Q
C-h i ; Choose Elisp
g font and TAB RET

Select the last paragraph about parameter `alpha' and copy it
using `M-w'.

M-x report-emacs-bug

Yank the copied text into the bug-report buffer.

Hit `C-c C-c'.  Choose to use an external mail client to
send the report.

When the mail client message window opens, select the
boiler-plate text:

*** E-Mail body has been placed on clipboard, please paste it here! ***

Paste the copied report-message text, replacing the selected
boiler-plate text.

This is what you get in the email message, to send as the
bug report:

     The =A1=AEalpha=A1=AF frame parameter can also be a cons cell =A1=AE(=
=A1=AEactive=A1=AF .
     =A1=AEinactive=A1=AF)=A1=AF, where =A1=AEactive=A1=AF is the opacity o=
f the frame when it is
     selected, and =A1=AEinactive=A1=AF is the opacity when it is not selec=
ted.

Curly quotes in the Info buffer have been replaced with
escape sequences such as =A1=AE.  This is in spite of the
fact that the mail-client window into which the text is
pasted is perfectly capable of handling Unicode chars such
as curly quotes.

(Just one more undesirable and unforeseen consequence of the
curly-quote-mania virus, I guess.  Time for yet another
hack-job workaround?)


In GNU Emacs 25.0.50.1 (i686-pc-mingw32)
 of 2015-09-05
Repository revision: 2330ca33a97867f2ea1123bcf7bfe5cfcc030b36
Windowing system distributor 'Microsoft Corp.', version 6.1.7601
Configured using:
 'configure --host=3Di686-pc-mingw32 --enable-checking=3Dyes,glyphs'

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND NOTIFY ACL GNUTLS LIBXML2 ZLIB
TOOLKIT_SCROLL_BARS

Important settings:
  value of $LANG: ENU
  locale-coding-system: cp1252

Major mode: Info

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-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
  buffer-read-only: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Composing main Info directory...done
Mark set [2 times]
Type C-x 1 to delete the help window, C-M-v to scroll help.
Char: =A1=AE (8216, #o20030, #x2018, file ...) point=3D1897434 of 3604579 (=
53%) <1894203-1899121> column=3D9

Load-path shadows:
None found.

Features:
(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
help-fns mail-prsvr mail-utils pp wid-edit descr-text help-mode
cl-loaddefs pcase cl-lib info easymenu dired time-date mule-util tooltip
eldoc electric uniquify ediff-hook vc-hooks lisp-float-type mwheel
dos-w32 ls-lisp disp-table w32-win w32-vars term/common-win tool-bar dnd
fontset image regexp-opt fringe tabulated-list newcomment elisp-mode
lisp-mode prog-mode register page menu-bar rfn-eshadow timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core frame
cl-generic cham georgian utf-8-lang misc-lang vietnamese tibetan thai
tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek romanian
slovak czech european ethiopic indian cyrillic chinese charscript
case-table epa-hook jka-cmpr-hook help simple abbrev minibuffer
cl-preloaded 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 w32notify w32 multi-tty
make-network-process emacs)

Memory information:
((conses 8 201120 12359)
 (symbols 32 29890 0)
 (miscs 32 66 267)
 (strings 16 33256 8135)
 (string-bytes 1 757007)
 (vectors 8 14837)
 (vector-slots 4 840990 7268)
 (floats 8 133 188)
 (intervals 28 34710 2066)
 (buffers 516 15))