Vulkan: Fix spammy best practices message A GPU WRITE->HOST barrier frequently issued when the GPU outputs to a host-visible buffer used the ALL_COMMANDS stage mask causing a best practices message. This message is suppressed in ANGLE, but shows up in RenderDoc and clutters the output. Bug: angleproject:5070 Change-Id: I59aa7f8c7b3bf2788a3f7ae0ab6abdb4d3cd175e Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3265606 Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>