MFC: r323382, MFV: r323381

Permit a deflateParams() parameter change as soon as possible.

This change fixes compression errors seen when the embedded Tomcat
web server of a UniFi Controller zlib compresses responses. Given
that Tomcat just uses Java/OpenJDK which in turn employs zlib for
its compression/decompression support, this bug might very well
affect other applications, too.

PR: 222136
Approved by: re (gjb)

MFC r311285,312335: zlib 1.2.11.

MFC r311275: Restructure libz.

Restructure libz, place vendor files in contrib/zlib like other third
party software, this provides more standarized import workflow and
makes future upgrades easier.

The following files are new with this commit:

zconf.h.in
zlib.map
zlib.pc.in

They are not connected to build, but were kept in tree for reference
for future maintenance.

All our local trivial changes were applied to contrib/zlib, and the
contrib/zlib vendor source code is intended to 100% match lib/libz
before this commit.

MFC after: 2 weeks

Add missing files in zlib 1.2.8.

Copy vendor/libz@250225 to vendor/zlib.

Vendor import of zlib 1.2.8.

Vendor import of zlib 1.2.7.

Vendor import of zlib 1.2.6.

Vendor import of zlib 1.2.5.

Import zlib 1.2.4.3 (trimmed).

Import zlib 1.2.4.1 beta (trimmed)

Remove unused part of contributed code.

Vendor import of zlib 1.2.4 (trimmed).

Flattern zlib vendor tree.

Vendor import of ZLib 1.2.3.

ZLib 1.2.2

Remove files that are no longer present in the zlib distribution from
the vendor branch.

Import zlib 1.2.1 (trimmed)

Import zlib 1.1.4 onto the vendor branch.

Import zlib 1.1.4 onto the vendor branch.

Import zlib 1.1.3 onto the vendor branch.

Obtained from: ftp.cdrom.com:/pub/infozip/zlib

Initial import of zlib-1.1.1

PR: 5869
Reviewed by: jdp

Official patch from infozip

This commit was manufactured by cvs2svn to create branch 'VENDOR-libz'.

Initial import of zlib-1.0.4