Remove deprecated WebGPU blend factors

The previous values are about to be removed from Dawn.

Bug: chromium:1199057
Change-Id: Iec6c4e4d641a99bceae975e68ab4b53ccdc75ef0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/445436
Auto-Submit: Brandon Jones <bajones@chromium.org>
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
1 file changed