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
reset( );
					return true;
				}
			}
			return false;
		}
		else
		{
			reset( );
			return false;
		}
	}
	/**
	 * Reset all the member data to their default value.
	 */
	private void reset( )
	{
		if ( firstPassRowNumberCounter  == secondPassRowNumberCounter )
		{
			doReset();
		}
	}
	/**
	 * 
	 *
	 */
	private void doReset()
	{
		firstPassRowNumberCounter = 0;
		secondPassRowNumberCounter = 0;