Bug 213981 [Automation] [Regression] Exception is thrown out when preview the attached report design [07]
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/internal/document/v4/ExtendedItemExecutor.java
Object rightEdge = sections[nextSection][1];
					if ( rightEdge != Segment.RIGHT_MOST_EDGE )
					{
						InstanceIndex rightIndex = (InstanceIndex) rightEdge;
						InstanceID rightId = rightIndex.getInstanceID( );
						if ( isSameInstance( rightId, childId ) )
						{
							useNextSection = true;
						}
					}
				}
				DocumentExtension docExt = (DocumentExtension) childContent
						.getExtension( IContent.DOCUMENT_EXTENSION );
				if ( docExt != null )
				{
					nextOffset = docExt.getNext( );
				}
			}
		}
		return childExecutor;
	}
	public IContent execute( )
	{
		if ( !executed )
		{
			executed = true;
			try
			{
				if ( offset != -1 )
				{