bug#17809: 24.4.50; Completions display

[martin rudalics]

> I tried to do this in bug#17809, but stumbled on the problem
> that resizing the window after filling is not supported
> by display-buffer actions alist.

`display-buffer' obviously expects the buffer to be "ready" at the time
of fitting the window to it.

>> For `with-temp-buffer-window' this means that we would have to fill the
>> buffer either via `temp-buffer-window-show-hook' or in QUIT-FUNCTION.
>
> Maybe filling the buffer is possible in QUIT-FUNCTION, but instead of
> `with-temp-buffer-window', `minibuffer-completion-help' uses
> `with-output-to-temp-buffer' that has no QUIT-FUNCTION arg.

Then `temp-buffer-show-hook' should cut it.

martin