[Xcb] patches from Arnaud Fontaine

[Barton C Massey]

In message <sa54pargcga.fsf at Orfeo.duckcorp.org> you wrote:
>  At  the  moment, xcb_get_wm_transient()  returns  a  pointer  on a  new
>  allocated    pointer    on     a    xcb_hints_t    structure    whereas
>  xcb_get_wm_size_hints() fills  the given xcb_size_hints_t  structure. I
>  think  that the  behavior of  both  should be  the same:  return a  new
>  allocated pointer on  a hints structure _or_ fills  the structure given
>  as a parameter.

I don't have a strong opinion on this.  If it's not causing
a problem of some kind, I'd be inclined to leave it alone, I
guess.  But if you want to make it consistent, that's fine
too---whichever convention folks think is better seems fine
to me.

Now that I think about it, though, this is probably an
instance of a more general question.  I suggest we adopt
Carl Worth's strategy for Cairo, and make things allocate
their own storage and provide destructor functions to free
it.  This is the kind of thing we'll want to do as we work
back through util getting ready for release.

	Bart