Bug 124610 Add a filter on a boolean computed column will cause error.
Description: Add a filter on a boolean computed column will cause error. Steps to reproduce: 1. New a BIRT sample data source and a dataset from table "orders" 2. Create a computed column with name="yes/no", type = any(no boolean for choose), value= if(row[1]%2==0){ true; }else{ false; } 3. Drag the dataset from Data Explorer to Layout 4. Select the table, click Filters tab in Property Editor. 5. Click Add button. 6. Select yes/no as Expression, Is True as Operator. 7. Save and preview. Expected result: Filter works. Actual result: Error0 : data.engine.ConvertToDataTypeError ( 1 time(s) ) detail : org.eclipse.birt.data.engine.core.DataException: can not be converted to class java.lang.Boolean.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/script/ScriptEvalUtil.java
{
			
			Object handle = expr.getHandle();
			if ( handle instanceof NEvaluator )
			{
				result =  Boolean.valueOf (((NEvaluator)handle).evaluate( cx, scope ));
			}
			else
			{
				ConditionalExpression ConditionalExpr = (ConditionalExpression) expr;
				Object expression = evalExpr( ConditionalExpr.getExpression( ), cx, scope, source, lineNo );
				Object Op1 = evalExpr( MiscUtil.constructValidScriptExpression ( ConditionalExpr.getOperand1() ), cx, scope, source, lineNo );
				Object Op2 = evalExpr( MiscUtil.constructValidScriptExpression ( ConditionalExpr.getOperand2() ), cx, scope, source, lineNo );
				result = evalConditionalExpr2( expression, ConditionalExpr.getOperator( ), Op1, Op2 ); 
			}
		}
		else
		{
			IScriptExpression jsExpr = (IScriptExpression) expr;
			if ( jsExpr.getText( ) != null && jsExpr.getHandle( ) != null )
			{
				result = ((CompiledExpression) jsExpr.getHandle( ) ).evaluate( cx, scope );
			}
			else
			{
				result = evaluateJSAsExpr( cx,
						scope,
						jsExpr.getText( ),
						source,
						lineNo );