Merge r1619383, r1619444, r1662245, r1662246 from trunk:

A misplaced check for inflation limits prevented limiting relatively
small inputs.  PR56872

Submitted By: Edward Lu 
Committed By: covener



mod_deflate: follow up to r1619383.

deflate_in_filter():
- use inflated bytes per inflate() call to compute the total output bytes,
- check zlib errors before limits,
- add missing check_ratio() when asked to flush.

deflate_out_filter():
- check ratio after each inflate() call.


mod_deflate: follow up to r1619383 and r1619444: CHANGES entry.

CHANGES: follow up to r1662245: Add PR number.
Submitted by: covener, ylavic, ylavic, ylavic
Reviewed/backported by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1669555 13f79535-47bb-0310-9956-ffa450edef68