Safari texture unit bug workaround (#1839)
Safari texture unit bug workaround (#1839)

* on safari desktop, clear out texture unit state once per frame
MicroWorldwide/PlayCanvas,sereepap2029/playcanvas,sereepap2029/playcanvas,playcanvas/engine,playcanvas/engine,aidinabedi/playcanvas-engine,aidinabedi/playcanvas-engine,sereepap2029/playcanvas,MicroWorldwide/PlayCanvas