Sync with chromium, primarily to shave the kOsFuchsia yak. Bug: angleproject:2475 Change-Id: I76ce607095d02e805a41f63315b4237e57f1cc4e Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1497392 Commit-Queue: Jamie Madill <jmadill@google.com> Reviewed-by: Jamie Madill <jmadill@google.com>
