D3D11: Fix ClearBufferiv with STENCIL.
D3D11: Fix ClearBufferiv with STENCIL.

For some reason we were using the second GLint value passed into the
method, when the spec says we should have a single clear value.

Noticed when adding tests for lazy robust resource init (tests will
be added in a subsequent patch).

BUG=angleproject:2107

Change-Id: Iadfc5072796255072bfb71ff1918253045e29576
Reviewed-on: https://chromium-review.googlesource.com/675049
Commit-Queue: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>
Reviewed-by: Frank Henigman <4f3ccfa167f952ff7263448ff4377acff6a23e5c@chromium.org>

ppy/angle,MSOpenTech/angle,MSOpenTech/angle,MSOpenTech/angle,ppy/angle,ppy/angle,MSOpenTech/angle,ppy/angle