* Improve the way to detect whether buckets in the filter chain need to be

  flushed by using the main requests bytes_count field instead of the
  subrequest field.

* Do not reset conn->need_flush. This prevents SegFaults from not flushing
  buckets in the filter chain.

PR: 45792


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@706921 13f79535-47bb-0310-9956-ffa450edef68