* We can ignore Z_BUF_ERROR in flush_libz_buffer because:

* We can ignore Z_BUF_ERROR in flush_libz_buffer because:
  When we call libz_func we can assume that

   - avail_in is zero (due to the surrounding code that calls
     flush_libz_buffer)
   - avail_out is non zero due to the fact that we just emptied
     the output buffer and stored it into a brigade

  So the only reason for Z_BUF_ERROR is that the internal libz
  buffers are now empty and thus we called libz_func one time
  too often. This does not hurt. It simply says that we are done.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@426793 13f79535-47bb-0310-9956-ffa450edef68