CL/Vulkan: Submit an empty command on command buffer reset On resetting the command buffer, the queue serial associated with it wont get signalled leading to causality issues. Instead submit an empty command to maintain queue serial timelines. Bug: angleproject:392934330 Change-Id: I53996b295d2744b58487e483dd45918e48f58c83 Signed-off-by: Gowtham Tammana <g.tammana@samsung.com> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6207673 Reviewed-by: Austin Annestrand <a.annestrand@samsung.com> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>