Function paint_armed_row_in 

pub fn paint_armed_row_in(
    scene: &mut Scene,
    transform: Affine,
    row: Rect,
    panel_radius: f64,
    inset: f64,
    theme: &Theme,
) -> AlphaColor<Srgb>

paint_armed_row inside a panel of panel_radius (a single-row menu’s single_row_radius).