bug#3210: face customization fails after set-face-attribute

[David Reitter]

Emacs -Q

(set-face-attribute 'default nil
                    :height 130
                    :family "Lucida Grande")
;; modifies default face

(customize-face 'default)
;; switch back manually to Monaco and "set for current session"

(make-frame-command)  ;; C-x 5 2
;; the new frame is shown in Lucida.  Why?


Upon inspection of some code, it appears unclear why `face-spec-set'  
iterates over all frame faces and sets the new spec there, but doesn't  
set the right property to set the face for future frames in case for- 
defface is t.