Include pathnames are passed unchanged to ID3DInclude objects so e.g.
if a file is included as "path/file.h" the full pathname will have
mixed slashes.

I don't think the difference between d3d10 depth/stencil and rendertarget
views is large enough to justify a separate type. Unfortunately that does make
the name "wined3d_rendertarget_view" slightly awkward.

This fixes a bug exposed by commit 415b8037.
In particular, wined3d_resource_update_draw_binding() uses the multisample
type to determine to appropriate draw binding, and since we never updated that
for the container, we could end up with an incorrect draw binding after a
device reset.