Bug 121687 Exception throws when export data in table which inside a grid cell.
Description: Exception throws when export data in table which inside a grid cell. Steps to reproduce: 1. insert a grid. 2. insert one table to one grid cell. 3. insert another table to the other grid cell. 4. export data in two tables. Expected result: Data are exported. Actual result: Exception in: ReportEngineService.getMetaData( )
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/parser/EngineIRVisitor.java
report.setPageSetup( pageSetup );
		
		
		SlotHandle bodySlot = handle.getBody( );
		for ( int i = 0; i < bodySlot.getCount( ); i++ )
		{
			apply( bodySlot.get( i ) );
			if ( currentElement != null )
			{
				report.addContent( (ReportItemDesign) currentElement );
			}
		}
		
		
		
		
		
	}
	/**
	 * setup the named expression map
	 * @param userProperties
	 * 			user defined named expressions in design file
	 * @param namedExpressions
	 *  		the data structure that hold named expressions
	 */
	private void setupNamedExpressions( DesignElementHandle handle, Map namedExpressions )
	{
		List userProperties = handle.getUserProperties( );
		if( userProperties == null || namedExpressions == null )