user32: Factorize graphics driver's WindowCreate and ShowWindowin user32.

[Dmitry Timoshkov]

"Pierre d'Herbemont" <pdherbemont at free.fr> wrote:

> My patch is wrong, but I am not sure we should leave ShowWindow in  
> the driver: It contains only Win32 calls (appart from  
> WINPOS_MinMaximize), and is indeed a wrapper for SetWindowPos. And  
> the exports are needed for CreateWindow, not ShowWindow.
> 
> What makes me move ShowWindow in user is the call to  
> WINPOS_MinMaximize which is shared with CreateWindow, and this one  
> needs the SetIconicState.

The problem is that for top level windows we need to route ShowWindow
actions to a Window Manager/Host Windowing System, so that actions
like minimize/maximize/restore would be properly handled. We don't
do this at the moment, but we need to.

-- 
Dmitry.