This PR condenses the namespaces in the tint/transform folder.
Change-Id: Idf448870ccf90f892b9186f7aab7bb0ac9deda17
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/86029
Auto-Submit: Dan Sinclair <dsinclair@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>