The MSDN is not totally correct: A8R8G8B8 and A1R5G5B5 also allow GetDC. The
main differences that have to be filtered out in d3d9.dll are GetDC on
A8B8G8R8, X8B8G8R8 and P8.

In general it might not be a bad idea to group GL specific data into a
separate struct, but IWineD3DSurfaceImpl is currently the only thing that
bothers. It doesn't get it quite right either, since e.g. the PBO isn't in
glDescriptor either.

There is no need to copy the frontbuffer to the screen when the backbuffer was
modified...

We can use the information from format_desc instead.

This creates a function for setting the texture name and one for
setting the texture target. The idea is that the texture target should
get set right after the surface is created, and won't change, while
generating a texture name can wait.

It has to update the whole surface, so NULL must be passed to 
x11_copy_to_screen. Fixes a regression in Red Alert.

This is a long-needed cleanup aimed at removing the ddraw_primary,
ddraw_window, ddraw_width and ddraw_height members from
IWineD3DDeviceImpl, which just do not belong there.  Destination
window and screen handling is supposed to be done by swapchains.