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
logger.entering( 
				ScriptEvalUtil.class.getName( ),
				"evalConditionalExpr",
				"evalConditionalExpr() resultObject="
				+ LogUtil.toString( resultObject )
				+ ", operator=" + operator
				+ ( resultOp1 == null? null: ( ", resultOp1=" + LogUtil.toString( resultOp1 ) ) )
				+ ( resultOp2 == null? null: ( ", resultOp2=" + LogUtil.toString( resultOp2 ) ) ) 
				);
		boolean result = false;
		switch ( operator )
		{
			case IConditionalExpression.OP_EQ :
			    result = compare( resultObject, resultOp1 ) == 0;
				break;
			case IConditionalExpression.OP_NE :
			    result = compare( resultObject, resultOp1 ) != 0;
				break;
			case IConditionalExpression.OP_LT :
				result = compare( resultObject, resultOp1 ) < 0;
				break;
			case IConditionalExpression.OP_LE :
				result = compare( resultObject, resultOp1 ) <= 0;
				break;
			case IConditionalExpression.OP_GE :
				result = compare( resultObject, resultOp1 ) >= 0;
				break;
			case IConditionalExpression.OP_GT :
				result = compare( resultObject, resultOp1 ) > 0;
				break;