Bug 315035 [Automation][Regression]Error happened while merge cells in grid when preview as pdf/ppt/ps
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/nLayout/area/impl/TableLayout.java
* @param cellArea
	 */
	public void resolveBorderConflict( CellArea cellArea, boolean isFirst )
	{
		IContent cellContent = cellArea.getContent( );
		int columnID = cellArea.getColumnID( );
		int colSpan = cellArea.getColSpan( );
		IRowContent row = (IRowContent) cellContent.getParent( );
		IStyle cellContentStyle = cellContent.getComputedStyle( );
		IStyle tableStyle = tableContent.getComputedStyle( );
		IStyle rowStyle = row.getComputedStyle( );
		IStyle columnStyle = getColumnStyle( columnID );
		IStyle preRowStyle = null;
		IStyle preColumnStyle = isRTL
				? getColumnStyle( columnID + 1 ) 
				: getColumnStyle( columnID - 1 );
		IStyle leftCellContentStyle = null;
		IStyle topCellStyle = null;
		RowArea lastRow = null;
		if ( rows.size( ) > 0 )
		{
			lastRow = (RowArea) rows.getCurrent( );
		}
		if ( lastRow != null )
		{
			preRowStyle = lastRow.getContent( ).getComputedStyle( );
			CellArea cell = lastRow.getCell( columnID );
			if ( cell != null && cell.getContent( ) != null )
			{
				topCellStyle = cell.getContent( ).getComputedStyle( );