Fix usage of deprecated wgpu::TextureUsage::OutputAttachment

Fixed: dawn:788
Change-Id: I2ec810fdd177aff61519192c234d5cb8cabe68d6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/409236
Auto-Submit: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Stephen White <senorblanco@google.com>
Reviewed-by: Stephen White <senorblanco@google.com>
1 file changed