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/PDFTableGroupLM.java
public PDFTableGroupLM( PDFLayoutEngineContext context,
			PDFStackingLM parent, IContent content, IReportItemExecutor executor )
	{
		super( context, parent, content, executor );
		IPDFTableLayoutManager lm = getTableLayoutManager( );
		assert(lm instanceof PDFTableLM);
		tableLM = (PDFTableLM) lm;
		tableLM.startGroup( (IGroupContent) content );
	}
	protected boolean traverseChildren( )
	{
		boolean childBreak = super.traverseChildren( );
		if ( !childBreak )
		{
			tableLM.endGroup( (IGroupContent) content );
		}
		return childBreak;
	}
	
	protected boolean checkAvailableSpace( )
	{
		boolean availableSpace = super.checkAvailableSpace( );
		if(availableSpace && tableLM != null)
		{
			tableLM.setTableCloseStateAsForced( );
		}
		return availableSpace;
	}
	
	public boolean layout()