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
itr = autoBindingExprs.entrySet( ).iterator( );
		while ( itr.hasNext( ) )
		{
			Map.Entry entry = (Entry) itr.next( );
			String exprName = (String) entry.getKey( );
			IBaseExpression baseExpr = (IBaseExpression) entry.getValue( );
			
			allAutoBindingExprs.add( new BindingColumn( exprName, baseExpr ) );
		}
	}
	/**
	 * @return
	 * @throws DataException
	 *             save error
	 */
	Map getColumnsValue( ) throws DataException
	{
		Map exprValueMap = new HashMap( );
		Map realValueMap = new HashMap( );
		for ( int i = 0; i < allManualBindingExprs.size( ); i++ )
		{
			List list = (List) allManualBindingExprs.get( i );
			Iterator it = list.iterator( );
			while ( it.hasNext( ) )
			{
				BindingColumn bindingColumn = (BindingColumn) it.next( );
				Object exprValue = evaluateValue( bindingColumn, MANUAL_BINDING );
				exprValueMap.put( bindingColumn.columnName, exprValue );
				if ( exprValue instanceof BirtException == false )
					realValueMap.put( bindingColumn.columnName, exprValue );