Bug 176582 "Show Lines as Curves" does not work correctly for Area Chart [0001]
Description: "Show Lines as Curves" does not work correctly for Area Chart. Build number: 2.2.0.v20070307-1128 Steps to reproduce: 1. New a Area Chart. 2. In "Format Chart" tab, select Series->Value (Y) Series, tick and untick "Show Lines as Curves" checkbox. Expected result: Null value point e is treated the same when tick and untick "Show Lines as Curves" checkbox. Actual result: Null value point e is treated differently (see the screenshot). Error log: N/A
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/render/BaseRenderer.java
int iSI = 0; 
			for ( int i = 0; i < elBase.size( ); i++ )
			{
				sdBase = (SeriesDefinition) elBase.get( i );
				alRuntimeSeries = sdBase.getRunTimeSeries( );
				
				if ( alRuntimeSeries.size( ) != 1 )
				{
					throw new ChartException( ChartEnginePlugin.ID,
							ChartException.PLUGIN,
							"exception.illegal.base.runtime.series.count", 
							new Object[]{
								new Integer( alRuntimeSeries.size( ) )
							},
							Messages.getResourceBundle( rtc.getULocale( ) ) );
				}
				se = (Series) alRuntimeSeries.get( 0 );
				brna[iSI] = ( se.getClass( ) == SeriesImpl.class ) ? new EmptyWithoutAxes( )
						: ps.getRenderer( se.getClass( ) );
				
				brna[iSI].set( cm, oComputations, se, sdBase );
				brna[iSI].set( rtc );
				brna[iSI].iSeriesIndex = iSI++;
				elOrthogonal = ( (SeriesDefinition) elBase.get( i ) ).getSeriesDefinitions( );
				for ( int j = 0; j < elOrthogonal.size( ); j++ )
				{
					sd = (SeriesDefinition) elOrthogonal.get( j );
					alRuntimeSeries = sd.getRunTimeSeries( );
					for ( int k = 0; k < alRuntimeSeries.size( ); k++ )
					{