CL/VK: Implement marker and barrier cmds Adding in last remaining marker and barrier cmds: clEnqueueMarker clEnqueueBarrier clEnqueueMarkerWithWaitList clEnqueueBarrierWithWaitList Bug: angleproject:8634 Change-Id: I67e03e379c3f9e40a31bcba34ea85e2739cc97b5 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5406617 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Austin Annestrand <a.annestrand@samsung.com> Reviewed-by: Geoff Lang <geofflang@chromium.org>