Crash in test d3d9:stateblock with warn+heap is a wine bug

[Stefan Dösinger]

With textures, the surface and the texture(the container) share one reference 
count. In the case of swapchains the swapchain is the container, so a 
GetBackBuffer would increment the swapchain's refcount to 2. So the swapchain 
wouldn't be destroyed before the backbuffer was released.

I am not sure if the texture refcounting applies to swapchains as well. Does 
the test test refcounts? If not, it might be worth adding a test. A fix would 
be in dlls/d3d9, not wined3d.