frame par'ms top + left ignored when frame invisible

[David Reitter]

In an Emacs -Q  (Carbon, current build), frame parameters "top" and  
"left" aren't set when the frame they are applied to is hidden:

In the following, the frame's width is adjusted correctly, but not its  
vertical position:

(let ((f (make-frame '((visibility . nil)))))
     (modify-frame-parameters f '((top . 30) (width . 100)))
     (make-frame-visible f))

If the frame is made visible before calling `modify-frame-parameters',  
things work as expected.