Update usage of deprecated Dawn typedefs

Bug: dawn:22
Change-Id: I7c0a4f77bc2c2df81ff4be091bf86569898a1ade
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/447216
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Stephen White <senorblanco@google.com>
Reviewed-by: Stephen White <senorblanco@google.com>
3 files changed