Bug 178519 Problems in multi-rows header
Please see the attachments.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/layout/pdf/BorderConflictResolver.java
* <ul>
 * <li>Borders with the 'border-style' of 'hidden' take precedence over all
 * other conflicting borders. Any border with this value suppresses all borders
 * at this location.
 * <li>Borders with a style of 'none' have the lowest priority. Only if the
 * border properties of all the elements meeting at this edge are 'none' will
 * the border be omitted (but note that <code>none</code> is the default value
 * for the border style.)
 * <li>If none of the styles are 'hidden' and at least one of them is not
 * 'none', then narrow borders are discarded in favor of wider ones. If several
 * have the same 'border-width' then styles are preferred in this order:
 * <code>double</code>, <code>solid</code>, <code>dashed</code>,
 * <code>dotted</code>, <code>ridge</code>, <code>outset</code>,
 * <code>groove</code>, and the lowest: <code>inset</code>.
 * <li>If border styles differ only in color, then a style set on a cell wins
 * over one on a row, which wins over a row group, column, column group and,
 * lastly, table. It is undefined which color is used when two elements of the
 * same type disagree.
 * </ul>
 * 
 * 
 */
public class BorderConflictResolver
{
	final static int POSITION_LEFT = 0;
	final static int POSITION_TOP = 1;
	final static int POSITION_RIGHT = 2;
	final static int POSITION_BOTTOM = 3;
	static HashMap styleMap = null;
	static