Fails presubmit if you need to run `./tools/run gen`
Change-Id: I05311cd668c5a1f4f484b25cc1367f680a9d24eb
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/110140
Commit-Queue: Ben Clayton <bclayton@google.com>
Auto-Submit: Ben Clayton <bclayton@google.com>
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
Kokoro: Ben Clayton <bclayton@google.com>