Vulkan: Use deferred allocation for swapchains when possible Bug: angleproject:7878 Change-Id: I539027f4fabe7a56f05280baee3772bc536791e6 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4088906 Reviewed-by: Ian Elliott <ianelliott@google.com> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Jeff Vigil <j.vigil@samsung.com>