Merge of r1861338,1862475,1862583,1862865,1863221,1863276 from trunk:

Merge of r1861338,1862475,1862583,1862865,1863221,1863276 from trunk:

  *) mod_http2: core setting "LimitRequestFieldSize" is not additionally checked on
     merged header fields, just as HTTP/1.1 does. [Stefan Eissing, Michael Kaufmann]

  *) mod_http2: fixed a bug that prevented proper stream cleanup when connection
     throttling was in place. Stream resets by clients on streams initiated by them
     are counted as possible trigger for throttling. [Stefan Eissing]

  *) mod_http2/mpm_event: Fixes the behaviour when a HTTP/2 connection has nothing
     more to write with streams ongoing (flow control block). The timeout waiting
     for the client to send WINODW_UPDATE was incorrectly KeepAliveTimeout and not
     Timeout as it should be. Fixes PR 63534. [Yann Ylavic, Stefan Eissing]

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1864126 13f79535-47bb-0310-9956-ffa450edef68