Function layout_2013::table_row::get_spanned_border_size

fn get_spanned_border_size(
    sizes: &[TableRowSizeData],
    row_index: usize,
    row_span: &mut u32,
) -> Au

Given an array of (_, cumulative_border_size), the index of the current row, and the >1 row_span of the cell, calculate the amount of border-spacing spanned by the row. In case the rowspan was larger than required, this will fix it up.