apple_cf is just a header, but we’ve got a BUILD.gn for
third_party/cpp-httplib, which is also just a header.
Change-Id: Ib42c25657b5964678d14682a0a802ebef0e4cb2f
Reviewed-on: https://chromium-review.googlesource.com/c/1489182
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
