bug#6796: 24.0.50; crash - regression in build of 2010-08-02, modify-frame-parameters

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

FWIW, this crash makes this build unusable for me.
There is no such crash in a build from 2010-07-19.
 
emacs -Q
 
1. Load frame-fns.el, then frame-cmds.el, then thumb-frm.el.
   These libraries are available here:
http://www.emacswiki.org/cgi-bin/wiki?action=index;match=%5C.(el%7Ctar)(%5C.gz)%
3F%24
 
2. (global-set-key [(control ?z)] 'iconify/map-frame)
 
This is the call that crashes (from the debugger):
 
* modify-frame-parameters(#<frame frame-cmds.el
  0x3f54400> ((tool-bar-position
  . top) (parent-id) (explicit-name . t) (display
  . "") (visibility . t) (icon-name) (window-id . "3409140") (top
  . 4) (left . 408) (buried-buffer-list) (buffer-list #<buffer
  frame-cmds.el> #<buffer *Minibuf-1*> #<buffer
  drews-lisp-20>) (unsplittable) (minibuffer) (modeline
  . t) (width . 104) (height . 59) (name
  . "frame-cmds.el") (background-mode . light) (display-type
  . color) (fringe . 0) (alpha) (scroll-bar-width
  . 17) (cursor-type
  . bar) (auto-lower) (auto-raise) (icon-type) (fullscreen) (title)
         (buffer-predicate) (tool-bar-lines
  . 0) (menu-bar-lines . 1) (right-fringe . 0) (left-fringe
  . 0) (line-spacing) (screen-gamma) (border-color
  . "black") (cursor-color . "Red") (mouse-color
  . "Red") (background-color . "LightBlue") (foreground-color
  . "Black") (vertical-scroll-bars
  . right) (internal-border-width . 0) (border-width . 2) (font
  . "-outline-Lucida
  Console-normal-normal-normal-mono-14-*-*-*-c-*-iso8859-1") (font-parameter
  . "-*-Lucida
  Console-normal-r-*-*-14-112-96-96-c-*-iso8859-1") (font-backend
  uniscribe gdi)))
 
 
 
In GNU Emacs 24.0.50.1 (i386-mingw-nt5.1.2600)
 of 2010-08-02 on 3249CTO
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (4.4) --no-opt --cflags -Ic:/xpm/include'