For whatever reason Calc uses a printer graphics context to
layout cell context. Without the initialized printer fonts,
you'll see broken cell content in Calc, until you edit them.

So now some part of the Qt5 GUI is painted by Cairo via the
psp::Printer graphics context.

Change-Id: Ib67c44abc952bc244f2c803d1dba8987ab618470
Reviewed-on: https://gerrit.libreoffice.org/66817
Tested-by: Jenkins
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>