Remove wgpu::Fence object from Dawn backend.

(It was unused.)

Bug: dawn:22
Change-Id: Ibcb31d35044c9875ab99304282bcbac584251257
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/409498
Commit-Queue: Stephen White <senorblanco@google.com>
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
1 file changed