[#746] Remove p.use3DContext
[#746] Remove p.use3DContext

kevinb7/processing-js,guazipi/processing-js,kevinb7/processing-js,jeresig/processing-js,jeresig/processing-js,guazipi/processing-js,corbanbrook/processing-js,corbanbrook/processing-js,baiyanghese/processing-js,baiyanghese/processing-js,jaredly/processing-js,corbanbrook/processing-js,jaredly/processing-js