This replaces the @override keyword that was previously used for
pipeline-overridable constants.
Support for pipeline-overridable constants in Dawn is hidden behind
the "disallow-unsafe-APIs" toggle, so we can make this change directly
instead of deprecating and continuing to support the old syntax.
Fixed: tint:1403
Change-Id: I9b2957a1e33b12772bfe449c0f3a31d929f8aa8b
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/80480
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: James Price <jrprice@google.com>