These tests were failing on SwapChain11 with errors relating to
the Depth Stencil backbuffer.

BUG=angle:856
BUG=435726

Change-Id: Idd371a380e9b302d7d5e40437e9d76589872b750
Reviewed-on: https://chromium-review.googlesource.com/237450Tested-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Brandon Jones <bajones@chromium.org>