internal/poll already imports io so use the io.Seek* constants instead
of defining them locally.
Change-Id: I91218c021e882e044503cae64b699e5a236ecc38
Reviewed-on: https://go-review.googlesource.com/c/go/+/623236
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com> Reviewed-by: Damien Neil <dneil@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Commit-Queue: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Ian Lance Taylor <iant@google.com>