Vulkan: Use current commandBuffer pointer We were using a passed in commandBuffer in ImageHelper::flushStagedUpdates which became invalid during the process of handling the flush upon which subsequent uses could cause problems when threading is enabled (and maybe when it's not as well, just harder to see.) Have ImageHelper::flushStagedUpdates use the current OutsideRenderPassCommandBuffer and the code will use the proper one. Bug: b/168144059 Change-Id: Ib9849efe9366cf61df5e68fd25d17df165dbd3a0 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2402354 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Courtney Goeltzenleuchter <courtneygo@google.com>