cocos2d/cocos2d-x — pull request #7900 by minggo (2014-08-28 03:44:05+00:00)
Title: not create Vec as possible for setting position

* Not create temple `Vec` in `Node::setPosition(float, float)`, `Node::setPositionX` and `Node::setPositionY()`
* Invoke `Node::setPosition(float, float)` if possible