The removed function had incorrect Windows implementation,
the return value was checked incorrectly.

Last use was removed in commit 573f76b3
https://chromium-review.googlesource.com/c/1042785

Bug: angleproject:2532
Change-Id: I66907fcb33041b097062208d53ca88752c05f9cb
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1664153Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Kimmo Kinnunen FI <kkinnunen@nvidia.com>