Bug 188029 Top face is missing in Area chart of 2D+ with negative values
Top face is missing in Area chart of 2D+ with negative values. Please see attached screenshot.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/computation/withaxes/StackedSeriesLookup.java
*
 * Contributors:
 * Actuate Corporation - initial API and implementation
 ***********************************************************************/
package org.eclipse.birt.chart.computation.withaxes;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.List;
import org.eclipse.birt.chart.computation.DataSetIterator;
import org.eclipse.birt.chart.engine.i18n.Messages;
import org.eclipse.birt.chart.exception.ChartException;
import org.eclipse.birt.chart.factory.RunTimeContext;
import org.eclipse.birt.chart.model.ChartWithAxes;
import org.eclipse.birt.chart.model.component.Axis;
import org.eclipse.birt.chart.model.component.Series;
import org.eclipse.birt.chart.model.data.SeriesDefinition;
import org.eclipse.birt.chart.plugin.ChartEnginePlugin;
import org.eclipse.emf.common.util.EList;
/**
 * Implements a double lookup data structure for stacked series. It also
 * maintains a min/max value for each unit needed to build the scale.
 */
public final class StackedSeriesLookup
{
	private final Hashtable htAxisToStackGroups;
	private final Hashtable htSeriesToStackGroup;
	private int iCachedUnitCount = 0;
	/**