Function arrow_key_event

src/plot_state.rs:1915–1917

(named: keyboard::key::Named, code: keyboard::key::Code)

        let mut hover_pick = None;
        let mut drag_event = None;
        for _ in 0..2 {
            state.handle_mouse_event(
                Event::ButtonPressed(mouse::Button::Left),
                mouse::Cursor::Available(Point::new(50.0, 50.0)),
                &widget,
                &mut hover_pick,