OpenCL/Vulkan: Add initial support for cmdQueue Introduce OpenCL command queue object creation for Vulkan backend in ANGLE. Bug: angleproject:8500 Change-Id: I08a63e91aa0ee75dd2be00c770f521c43a3f83b3 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5233367 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Austin Annestrand <a.annestrand@samsung.com>