When CacheKeyBaseURL is not use, the ":" is kept.
So, be consistent when building the key and keep the ":" in all cases.
PR 53915 [Rein Tollevik <rein basefarm.no>]
+ merge 2 lines of a comment to have it more compact
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1851146 13f79535-47bb-0310-9956-ffa450edef68