Merge r1775487 from trunk:

fix crash in util_fcgi.c

 *) mod_proxy_fcgi, mod_fcgid: Fix crashes in ap_fcgi_encoded_env_len() when
    modules add empty environment variables to the request. PR60275.
    [<alex2grad AT gmail.com>]

Submitted By: <alex2grad AT gmail.com>]
Committed By: covener



Submitted by: covener
Reviewed by: covener, jim, wrowe


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1778050 13f79535-47bb-0310-9956-ffa450edef68