bug#7368: display-buffer a softly dedicated window

[martin rudalics]

>> It could fail because it falls back on `display-buffer' when the
>> selected window is a minibuffer window or dedicated.  `pop-to-buffer'
>> and the remaining members of the `switch-to-buffer' family always fail
>> to use a weakly dedicated window.
>>
>
> I mean override soft-dedication *inside* display-buffer. And
> switch-to-buffer actually doesn't fail to override "softly dedicated"
> window (see my examle).

It doesn't fail in your example.  I explained above how it can fail.

But rather than thinking about how to "fix" this I'd try to find out why
`display-buffer' is called _before_ burying the completions buffer.  The
plain fact that the completions buffer can be reused by `display-buffer'
indicates that it is no more useful at the time `display-buffer' gets
called.

martin