Vulkan: Add display creation, test and extension. With this CL we have the ability to create Vulkan test configs and run basic tests, although the only thing that works is creating a Vulkan Renderer using the extension. BUG=angleproject:1319 Change-Id: I8ad17bba01241334be7da16e68fea38762ca6a20 Reviewed-on: https://chromium-review.googlesource.com/367750 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Corentin Wallez <cwallez@chromium.org>