When creating the pbuffer, Chromium specifies EGL_WIDTH and EGL_HEIGHT
attributes that are unnecessary because they are extracted from the
D3D11 texture passed as <buffer> to eglCreatePbufferFromClientBuffer.

This is a regression test for crbug.com/794086 where a change to
ValidateCreatePbufferFromClientBuffer made EGL_WIDTH and EGL_HEIGHT
invalid for <buftype> EGL_D3D_TEXTURE and caused Chromium to fail
creating the pbuffer, causing all black rendering.

BUG=chromium:794086

Change-Id: I262fd0991e0f46f255aeac25528ddb4a62fa1309
Reviewed-on: https://chromium-review.googlesource.com/822296Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>