Bug 123726 "Top n", "Bottom n" in highlight dialog doesn't work.
Description: "Top n", "Bottom n" in highlight dialog doesn't work. Steps to reproduce: 1. Add a highlight for a table. 2. Set highlight rule: "account_id", "top n", "3", let its font color red. 3. Preview the report, it doesn't work. Attached is design file.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/script/NEvaluator.java
private IScriptExpression n_expr;
	
	private FilterPassController filterPassController;
	protected static final String nullValueReplacer = "{NULL_VALUE_!@#$%^&}";
	/**
	 * Create a new instance to evaluate the top/bottom expression
	 * @param operator 
	 * @param op_expr operand expression
	 * @param n_expr expression to yield N 
	 * @return
	 */
	public static NEvaluator newInstance( int operator, IScriptExpression op_expr, 
			IScriptExpression n_expr, FilterPassController filterPassController  )
	 	throws DataException
	{
		NEvaluator instance = null;
		switch ( operator )
		{
			case IConditionalExpression.OP_TOP_N :
				instance = new TopNEvaluator();
				instance.n_percent = false;
				break;
			case IConditionalExpression.OP_TOP_PERCENT:
				instance = new TopNEvaluator( );
				instance.n_percent = true;
				break;
			case IConditionalExpression.OP_BOTTOM_N:
				instance = new BottomNEvaluator( );
				instance.n_percent = false;
				break;