Bug 207268 Add visibility option for plot within axes
For chart with axes, we should make plot within axes invisible. Meantime, other plots, such as axes, legend and title, should be visible. This enhancement doesn't include UI change, and it is required for cross tab integration.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/render/AxesRenderer.java
"exception.unsupported.compare.unknown.objects", 
						new Object[]{
								de1, de2
						},
						Messages.getResourceBundle( getRunTimeContext( ).getULocale( ) ) ); 
			}
		}
		throw new ChartException( ChartEnginePlugin.ID,
				ChartException.DATA_FORMAT,
				"exception.unsupported.compare.different.objects", 
				new Object[]{
						de1, de2
				},
				Messages.getResourceBundle( getRunTimeContext( ).getULocale( ) ) ); 
	}
	private static final TextAlignment anchorToAlignment( Anchor anc )
	{
		final TextAlignment ta = TextAlignmentImpl.create( ); 
		
		
		if ( anc == null )
		{
			return ta;
		}
		
		switch ( anc.getValue( ) )
		{
			case Anchor.NORTH :
			case Anchor.NORTH_EAST :
			case Anchor.NORTH_WEST :