types2 handles all constant-related bounds checks in user Go code now,
so it's safe to remove the check in IndexConst function.
Change-Id: I9116493f191c4df1cce7e43c8ac3dc5bf020fd5c
Reviewed-on: https://go-review.googlesource.com/c/go/+/611675
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com> Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Tim King <taking@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@golang.org>