ozone: scenic: Enable vulkan in the sandbox

This is necessary to use the GPU through vulkan.

Bug: 861853
Test: ozone_demo --ozone-platform=scenic --enable-vulkan (with full series)

Change-Id: I7eac180b9c8592f6f5c10799fa845331bda16ec4
Reviewed-on: https://chromium-review.googlesource.com/1188971
Commit-Queue: Michael Spang <spang@chromium.org>
Reviewed-by: Sergey Ulanov <sergeyu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#586300}
2 files changed