internal/poll: always use SetFileCompletionNotificationModes on non-socket handles
SetFileCompletionNotificationModes can be unconditionally called on
non-socket handles.
The Windows poll.FD implementation still doesn't support non-socket
pollable handles yet, so this CL doesn't change any behavior.
Support for pollable non-socket handles will come in subsequent CLs.
For #19098.
Change-Id: I811a61497cfbb26acb566c20367d212335b9d551
Reviewed-on: https://go-review.googlesource.com/c/go/+/660495 Reviewed-by: Damien Neil <dneil@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Damien Neil <dneil@google.com>