Fix a bug in context creating in ChemObjPainter
Fix a bug in context creating in ChemObjPainter

partridgejiang/Kekule.js,partridgejiang/Kekule.js,partridgejiang/Kekule.js,partridgejiang/Kekule.js,partridgejiang/Kekule.js,partridgejiang/Kekule.js