Bug 201017 TopN, TopPercent, BottomPercent filters will lead NPE when the values contains NULL[07]
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/script/NEvaluator.java
{
		firstPassRowNumberCounter++;
		if ( valueList == null )
		{
			valueList = new BasicCachedArray( N );
			rowIdList = new BasicCachedArray( N );
			
		}
		populateValueListAndRowIdList( value, N );
		return true;
	}
	/**
	 * @param value
	 * @param N
	 * @throws DataException
	 */
	private void populateValueListAndRowIdList( Object value, int N ) throws DataException
	{
		assert N>=0;
		int activeCount = N < this.firstPassRowNumberCounter? N:this.firstPassRowNumberCounter;
		for( int i = 0; i < activeCount; i++ )
		{
			if( value == null )
				value = nullValueReplacer;
			if( valueList.get( i ) == null )
			{
				valueList.set( i, value);
				rowIdList.set( i, new Integer( firstPassRowNumberCounter ) );
				break;
			}