bug#29272: 26.0.90; "C-h k C-mouse-3" followed by menu selection asks for more keys

[Eli Zaretskii]

To reproduce:

  emacs -Q
  C-h k C-mouse-3

This pops up a Lisp Interaction Mode menu.  Select some item from the
menu.  The expected result is to show in *Help* the description of the
command selected from the menu.  Instead, you are prompted again for a
key or a mouse click.

"C-h l" shows this:

  C-h k [describe-key]
  <C-down-mouse-3> <indent-pp-sexp> <help-echo> <help-echo>

(I'm guessing help-echo comes from the menu items traversed by the
mouse while selecting the item.)

This works in Emacs 25.2, so it's a recent regression.

In GNU Emacs 26.0.90 (build 1, i686-pc-mingw32)
 of 2017-10-12 built on HOME-C4E4A596F7
Windowing system distributor 'Microsoft Corp.', version 5.1.2600
Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Type C-x 1 to delete the help window.

Configured using:
 'configure --prefix=/d/usr --with-wide-int --with-modules
 --enable-checking=yes,glyphs 'CFLAGS=-Og -gdwarf-4 -g3''

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND NOTIFY ACL GNUTLS LIBXML2 ZLIB
TOOLKIT_SCROLL_BARS MODULES LCMS2

Important settings:
  value of $LANG: ENU
  locale-coding-system: cp1255

Major mode: Lisp Interaction

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

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny seq byte-opt gv
bytecomp byte-compile cconv dired dired-loaddefs format-spec rfc822 mml
mml-sec password-cache epa derived epg epg-config gnus-util rmail
rmail-loaddefs mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums
mm-util mail-prsvr mail-utils cl-extra help-fns radix-tree help-mode
easymenu cl-loaddefs cl-lib elec-pair time-date mule-util tooltip eldoc
electric uniquify ediff-hook vc-hooks lisp-float-type mwheel dos-w32
ls-lisp disp-table term/w32-win w32-win w32-vars term/common-win
tool-bar dnd fontset image regexp-opt fringe tabulated-list replace
newcomment text-mode elisp-mode lisp-mode prog-mode register page
menu-bar rfn-eshadow isearch timer select scroll-bar mouse jit-lock
font-lock syntax facemenu font-core term/tty-colors 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 composite charscript charprop
case-table epa-hook jka-cmpr-hook help simple abbrev obarray 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 lcms2
multi-tty make-network-process emacs)

Memory information:
((conses 16 103039 10652)
 (symbols 56 21441 1)
 (miscs 48 40 97)
 (strings 16 32209 1748)
 (string-bytes 1 779452)
 (vectors 16 14316)
 (vector-slots 8 648524 8150)
 (floats 8 52 222)
 (intervals 40 292 114)
 (buffers 880 12))