Dawn: remove a faulty assert.

Change-Id: I2cecddf98bcc44a7d3970463518bffa079038971
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/233568
Reviewed-by: Stephen White <senorblanco@chromium.org>
Commit-Queue: Stephen White <senorblanco@chromium.org>
1 file changed