GitLab

This is a reland of d86a6561

Original change's description:
> mac: roll to 10.13 SDK
> 
> This change causes the default hermetic SDK to be version 10.13 (aka Xcode 9.3).
> This also bumps the minimum build host version to 10.13.2, since that
> is the earliest version on which Xcode 9.3 runs.
> 
> Bug: 780980
> Change-Id: I6da3f7d3a060a22d71d5ee18bb88f51d5aedb0a2
> Reviewed-on: https://chromium-review.googlesource.com/c/1394742
> Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
> Reviewed-by: Nico Weber <thakis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#620032}

Bug: 780980
Change-Id: Iea403cc2dcbfc56ce54a6ad72ca4d2729b520fd0
Reviewed-on: https://chromium-review.googlesource.com/c/1436942
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#626106}