[FIX] Fix bug which can lead to NaN drawOrder in element
[FIX] Fix bug which can lead to NaN drawOrder in element

playcanvas/engine,sereepap2029/playcanvas,aidinabedi/playcanvas-engine,sereepap2029/playcanvas,MicroWorldwide/PlayCanvas,sereepap2029/playcanvas,aidinabedi/playcanvas-engine,MicroWorldwide/PlayCanvas,playcanvas/engine