Vulkan: Prune superseded updates during host-image-copy Bug: angleproject:42266771 Change-Id: I7aa8e85720a54537389df615b575ddfa9951770d Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6462475 Reviewed-by: Yuxin Hu <yuxinhu@google.com> Reviewed-by: Cody Northrop <cnorthrop@google.com> Auto-Submit: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Cody Northrop <cnorthrop@google.com>