If the texture attachment doesn't have a stencil aspect, we can
set stencilReadOnly flag in RenderPassDepthStencilAttachment as
we want. And it is totally ignored and it doesn't impact whether
the depth/stencil attachment is readonly or not.
That's true for depthReadOnly flag upon a stecil-only format like
stencil8, but we haven't support stencil8 yet.
Bug: dawn:485
Change-Id: If0a21250ce7cc7a1ad9cc17a05ecf64d05342cd0
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/67962
Commit-Queue: Kai Ninomiya <kainino@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>