Revert r1844928 and follow up r1844942.

Actually *len can be > 0 here, at least without a change I'm working on but now
think should be discussed first probably. Anyway r1844928 alone is broken, just
rollback for now.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1845064 13f79535-47bb-0310-9956-ffa450edef68