Vulkan: SwiftShader now getting correct sample positions This was fixed in SwiftShader and I verified it Bug: angleproject:4213 Change-Id: I6f591b81a62ec4c586d4abb7e6a2345794602833 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2025066 Reviewed-by: Ian Elliott <ianelliott@google.com> Commit-Queue: Ian Elliott <ianelliott@google.com>