We're in progress replicating the AFS volume for tarballs to a
remote location for added redundancy, but this is blocking updates
of all the read-only replicas until it completes and we're unsure
how long that will take. In the meantime, serve content from the
writeable path instead of the read-only replica path so we're not
stuck with outdated content on the site.
Change-Id: I6e0333bdb9717a724fd29adffc3df6e6c5da1558
542c898021