Function layout_2013::display_list::background::tile_image_axis

fn tile_image_axis(
    repeat: BackgroundRepeatKeyword,
    position: &mut Au,
    size: &mut Au,
    tile_size: &mut Au,
    tile_spacing: &mut Au,
    offset: Au,
    clip_origin: Au,
    clip_size: Au,
)

For either the x or the y axis adjust various values to account for tiling.

This is done separately for both axes because the repeat keywords may differ.