This CL adds const-eval for `min` and `max`.
Bug: tint:1581
Change-Id: Ica68ba312f21767c46d57d83570ddc72ee857231
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/110166
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>