Improve change-property test
Improve change-property test

- So it also tests PropertyChange event notification

sidorares/node-x11,wpp2014/node-x11,wpp2014/node-x11,15lyfromsaturn/node-x11,sidorares/node-x11,Arteris/node-x11,santigimeno/node-x11,15lyfromsaturn/node-x11,15lyfromsaturn/node-x11,wpp2014/node-x11,sidorares/node-x11,Arteris/node-x11,santigimeno/node-x11