`Rect::round_out` is either incorrect or documented wrong

The documentation claims that this function:

Converts into an IntRect rounding outwards.

However, the following code prints Some(IntRect { x: 1, y: 1, width: 2, height: 2 }) which is rounding the right and bottom edges inwards:

let r = Rect::from_ltrb(1.8, 1.8, 3.1, 3.1).unwrap();
println!("{:?}", r.round_out());

src/scan/path_aa.rs uses the "correct" implementation and calls out that Rect::round_out returns the wrong result.

I would suggest that the current implementation is useless, and replace it with the one from path_aa.rs that actually rounds out.

Start by reproducing the example and reading Rect::round_out alongside the alternative implementation in src/scan/path_aa.rs. Determine whether the implementation or its documentation is wrong, then align the behavior and documentation so rounding extends all four edges outward and the example produces the expected result.