[gtkada] Storage leak when changing button graphics

[christoph.grein at eurocopter.com]

Manuel
> 
> I image you need to call Unref(Mask) and Unref(Graphic) in your

Thanx, that was it :-)

> case as well. Or don't create the pixmaps again every time you
> need the button changed, but only once.

Your're right of course, and I'll do that now, but I wanted to locate the leak 
first.

Christoph

> Manuel