On the 2.4.x branch:

Merged /httpd/httpd/trunk:r1793533,1794049

mod_http2: fail requests without ERROR log in case we need to read interim
     responses and see only garbage. This can happen if proxied servers send
     data where none should be, e.g. a body for a HEAD request.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1794052 13f79535-47bb-0310-9956-ffa450edef68