Bug 156166 Error occour when previewing attached report in web viewer.
Decription:Error occour when previewing attached report in web viewer. Steps to reproduce: 1.run attached reports in web viewer. Expeceted results: preview properly Actual results: Error occour when previewing the reports in web viewer while it works properly in html and PDF
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/BindingColumnsEvalUtil.java
private EvalHelper evalHelper;
	
	private final static int MANUAL_BINDING = 1;
	private final static int AUTO_BINDING = 2;
	/**
	 * @param ri
	 * @param scope
	 * @param saveUtil
	 * @param serviceForResultSet
	 */
	BindingColumnsEvalUtil( IResultIterator ri, Scriptable scope,
			RDSaveHelper saveUtil, List manualBindingExprs, Map autoBindingExprs )
	{
		this.odiResult = ri;
		this.scope = scope;
		this.saveHelper = saveUtil;
		
		try
		{
			this.isBasedOnRD = ExprMetaUtil.isBasedOnRD( ri.getResultClass( ) );
			if ( this.isBasedOnRD == true )
				this.evalHelper = new EvalHelper( ri );
		}
		catch ( DataException e )
		{
			
		}
		this.initBindingColumns( manualBindingExprs, autoBindingExprs );
	}
	/**