closed #2307: Adding cc.PhysicsSprite.prototype.getBody in jsb_cocos2d_extension.
The issue was fixed at https://github.com/cocos2d/cocos2d-x/pull/2869 .
Reported at http://www.cocos2d-x.org/boards/20/topics/25430?r=31702
Merge pull request #3163 from dumganhar/develop

closed 2307: Adding cc.PhysicsSprite.prototype.getBody in jsb_cocos2d_extension.