cocos2d/cocos2d-x — pull request #6852 by xhcnb (2014-05-20 13:03:20+00:00)
Title: fix: Subclass of Scene can't call this->scheduleUpdate() with physics feature.

Refactor Scene with physics feature.
If use 'update(float)' and 'scheduleUpdate' will cause subclass of Scene can't call 'this->scheduleUpdate()', because it has already called in super class. That's confused API design.
So, I think there should be an separate update function for Physics Scene.