This is a step towards deferring adding the handle to IOCP until the
first IO operation.
FD.pollable() obscures the fact that it is really checking if the handle
is associated with the IOCP. This doesn't need to be a function that
checks multiple conditions. It can be a simple boolean field that tracks
whether the handle is associated with the IOCP or not.
For #76391
Cq-Include-Trybots: luci.golang.try:gotip-windows-amd64-longtest,gotip-windows-amd64-race
Change-Id: I3ee6532f8a387fb5cfae8ae3d20ea9569f585e71
Reviewed-on: https://go-review.googlesource.com/c/go/+/742282 Reviewed-by: Michael Pratt <mpratt@google.com> Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Damien Neil <dneil@google.com>