Function rsvg::text::add_pango_attributes

fn add_pango_attributes(
    attr_list: &AttrList,
    props: &FontProperties,
    start_index: usize,
    end_index: usize,
    font_size: PangoUnits,
    letter_spacing: PangoUnits
)

Adds Pango attributes, suitable for a span of text, to an AttrList.