copy-face, delete-frame -> invalid face

[David Reitter <david.reitter@gmail.com>]

Executing the following:

(let ((nf (make-frame)))
   (copy-face 'default 'new-face (selected-frame) nf)
   (delete-frame nf)
   (make-frame))

will produce the error below, and it will render Emacs unusable until  
a restart, because the faulty new-face persists and causes the problem  
whenever a new frame is made.

Debugger entered--Lisp error: (error "Invalid face" new-face)
   internal-get-lisp-face-attribute(new-face :family #<frame Emacs@scarlett.lan 
  0x76a710>)
   face-attribute(new-face :family #<frame Emacs@scarlett.lan 0x76a710>)
   face-attr-match-p(new-face nil #<frame Emacs@scarlett.lan 0x76a710>)
   face-spec-match-p(new-face nil #<frame Emacs@scarlett.lan 0x76a710>)
   frame-set-background-mode(#<frame Emacs@scarlett.lan 0x1f102e0>)
   x-create-frame-with-faces(nil)
   make-frame()





In GNU Emacs 22.1.50.1 (i386-apple-darwin8.10.1, Carbon Version 1.6.0)
  of 2007-10-15 on plume.sr.unh.edu
Windowing system distributor `Apple Inc.', version 10.5.1
configured using `configure  '--without-x' '--prefix=/usr/local''

Important settings:
   value of $LC_ALL: nil
   value of $LC_COLLATE: nil
   value of $LC_CTYPE: nil
   value of $LC_MESSAGES: nil
   value of $LC_MONETARY: nil
   value of $LC_NUMERIC: nil
   value of $LC_TIME: nil
   value of $LANG: nil
   locale-coding-system: iso-8859-1
   default-enable-multibyte-characters: t

Major mode: Debugger

Minor modes in effect:
   encoded-kbd-mode: t
   tooltip-mode: t
   tool-bar-mode: t
   mouse-wheel-mode: t
   menu-bar-mode: t
   file-name-shadow-mode: t
   global-font-lock-mode: t
   font-lock-mode: t
   blink-cursor-mode: t
   unify-8859-on-encoding-mode: t
   utf-translate-cjk-mode: t
   auto-compression-mode: t
   line-number-mode: t

Recent input:
<down-mouse-1> <drag-mouse-1> C-y C-x C-e <switch-frame>
<help-echo> <help-echo> <down-mouse-1> <mouse-1> <help-echo>
<menu-bar> <help-menu> <send-emacs-bug-report>

Recent messages:
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