Merge r1895914, r1895921 from trunk:

Merge r1895914, r1895921 from trunk:

  *) http: Enforce that fully qualified uri-paths not to be forward-proxied
     have an http(s) scheme, and that the ones to be forward proxied have a
     hostname, per HTTP specifications.
     trunk patch: http://svn.apache.org/r1895914
                  http://svn.apache.org/r1895921
     2.4.x patch: https://patch-diff.githubusercontent.com/raw/apache/httpd/pull/286.patch
     backport PR: https://github.com/apache/httpd/pull/286
     +1: ylavic, minfrin, gbechis

mod_proxy: Detect unix: scheme syntax errors at load time.

* modules/proxy/mod_proxy.c(add_pass, add_member, set_proxy_param,
                            proxysection):
  Check return value of ap_proxy_de_socketfy().

* modules/proxy/proxy_util.c(ap_proxy_get_worker_ex):
  Check return value of ap_proxy_de_socketfy().

http: Enforce that fully qualified uri-paths not to be forward-proxied
      have an http(s) scheme, and that the ones to be forward proxied have a
      hostname, per HTTP specifications.

The early checks avoid failing the request later on and thus save cycles
for those invalid cases.

Submitted by: ylavic
Reviewed by: ylavic, minfrin, gbechis
Closes #286

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1895955 13f79535-47bb-0310-9956-ffa450edef68