Replace a POSIX API call not supported by Fuchsia. Bug: chromium:809201 Change-Id: Iafc2e7efe92bcb977e5185901c073e499114a9f4 Reviewed-on: https://chromium-review.googlesource.com/903261 Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Jamie Madill <jmadill@chromium.org>