Merge r1843426 from trunk:

mod_http2: adding defensive code for stream EOS handling, in case the request handler
     missed to signal it the normal way (eos buckets). Addresses github issues 
     https://github.com/icing/mod_h2/issues/164, https://github.com/icing/mod_h2/issues/167
     and https://github.com/icing/mod_h2/issues/170. 


Submitted by: icing
Reviewed by: icing, ylavic, jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1843468 13f79535-47bb-0310-9956-ffa450edef68