[Piglit] [PATCH 2/2] arb_robustness: add test for empty vbo

[Erik Faye-Lund]

On Wed, 2018-12-05 at 12:31 +0100, Erik Faye-Lund wrote:
> Signed-off-by: Erik Faye-Lund <erik.faye-lund at collabora.com>
> ---

Just a tiny bit of background:
- ARB_robustness defines what happens with zero-sized buffers (should
return all-zero values).
- This test currently pass on i965.
- ...but fail on all gallium drivers. I'm working on patches for the
latter.