Rearrange step() to be faster in V8
Rearrange step() to be faster in V8

JershXL/gbajs,matthewbauer/gbajs,JershXL/gbajs,matthewbauer/gbajs,ElliottAYoung/gbajs,endrift/gbajs,endrift/gbajs,ElliottAYoung/gbajs