On the fsfs-improvements branch, block r1511815 from being merged from trunk.

That revision addresses a "Unused function" problem, but the function is not
unused on this branch.

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/fsfs-improvements@1511817 13f79535-47bb-0310-9956-ffa450edef68