Add compression support for GZ through ZCodec

ZCodec uses zlib to deflate. That file has code
to allow for compressing to GZ but it's wrapped in defines.

There's places in code where there's need for zlib headers
(ie. svx/source/gallery2/codec.cxx:71) and there will be need
for gz header compression when EMZ/WMZ/SVGZ export support
is added.

Made compression functions care about mbGzLib bool. Also added
a SetCompressionMetadata function to set metadata which are otherwise
impossible to know (such as filename, which is needed in the header)

Change-Id: Ic01050262b0b15e0632564b139c66656afac4611
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/135213
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

0 files changed, 0 insertions, 0 deletions