Fixed WebRenderer.preRender() to not violate its return-type contract.
Fixed WebRenderer.preRender() to not violate its return-type contract.

joshuabrown-ellation/libjass,joshuabrown-ellation/libjass,Arnavion/libjass,Arnavion/libjass,Arnavion/libjass,joshuabrown-ellation/libjass