Bug 176457 Use container's column bindings in chart editor
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/ReportDataServiceProvider.java
public String[] getAllDataSets( )
	{
		List list = getReportDesignHandle( ).getVisibleDataSets( );
		String[] names = new String[list.size( )];
		for ( int i = 0; i < names.length; i++ )
		{
			names[i] = ( (DataSetHandle) list.get( i ) ).getQualifiedName( );
		}
		return names;
	}
	public final String[] getPreviewHeader( ) throws ChartException
	{
		Iterator iterator = getColumnDataBindings( );
		ArrayList list = new ArrayList( );
		while ( iterator.hasNext( ) )
		{
			list.add( ( (ComputedColumnHandle) iterator.next( ) ).getName( ) );
		}
		return (String[]) list.toArray( new String[list.size( )] );
	}
	public final List getPreviewData( ) throws ChartException
	{
		return getPreviewRowData( getPreviewHeader( true ), -1, true );
	}
	private String[] getPreviewHeader( boolean isExpression )
			throws ChartException
	{
		String[] exps = getPreviewHeader( );
		if ( isExpression )
		{