This also involves a reorganization of the code into its own
subdirectory.
BUG=tint:253
Change-Id: If05018da2662e923e659b485576704f3a6bcd062
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/30340
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: dan sinclair <dsinclair@chromium.org>