Some buggy SVG interpreters can't handle 0-length ovals. In this case,
they are meant to be circles, so we can export as circles in our
plotter.
Fixes https://gitlab.com/kicad/code/kicad/issues/3995
(cherry picked from commit e38ab6c699)
When plotting in Eeschema, various elements may be filled with either
the foreground or background colors. The fill mode is rather unique,
requiring un-stroked pie wedges for arcs and both closed and open filled
polylines.
Fixes: lp:1840769
* https://bugs.launchpad.net/kicad/+bug/1840769