Bug 152560 PDF doesn't display bottom Border in inner group footer properly
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/layout/pdf/PDFTableLM.java
return true;
		}
		return false;
	}
	public boolean addArea( IArea area )
	{
		assert ( area instanceof RowArea );
		RowArea row = (RowArea) area;
		lastRowArea = row;
		return super.addArea( area );
	}
	protected void updateAllUnresolvedCellArea(ArrayList lastDropCells )
	{
		removeDropCells(lastDropCells);
	}
	public void updateUnresolvedCell( int groupLevel, boolean dropAll )
	{
		String dropType = dropAll ? "all" : "detail"; 
		int dropValue = this.createDropID( groupLevel, dropType );
		removeDropAreaBySpan( dropValue );
		for ( int i = 0; i < this.columnNumber; i++ )
		{
			if ( currentRowContent[i] != null )
			{
				if ( dropValue == currentRowContent[i].rowSpan )
				{
					currentRowContent[i] = null;
				}
			}
		}