RsvgNodeRect: Use RsvgPathBuilder instead of building/parsing a path string
RsvgNodeRect: Use RsvgPathBuilder instead of building/parsing a path string

Signed-off-by: Federico Mena Quintero <4999915a961edfd7686112c2935288e1266eae14@gnome.org>

GNOME/librsvg,GNOME/librsvg,GNOME/librsvg,GNOME/librsvg