Function draw_loading 

pub fn draw_loading(
    scene: &mut Scene,
    transform: Affine,
    text: &mut TextRenderer,
    theme: &Theme,
    rect: Rect,
    label: &str,
)

Draw the quiet panel that stands in rect for a surface whose code is on its way: the raised surface colour, and label (a toolkit message key) in the body text, inset as a panel’s content is.