This is not 100% correct (the exceptions for mat2 and friends are not
implemented yet), but gets more tests passing in Dawn.
Bug: tint:1415
Change-Id: Ia11c63a5236f35e724431a65ddb6ef3c598775d0
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/79380
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: David Neto <dneto@google.com>
Commit-Queue: Stephen White <senorblanco@chromium.org>