We can get a NullPointerException in some race condition cases if the children variable is not allocated before it is used.  Added childrenAlloc() and some defensive coding needed to guard against this possibility.
We can get a NullPointerException in some race condition cases if the children variable is not allocated before it is used.  Added childrenAlloc() and some defensive coding needed to guard against this possibility.
amoikevin/cocos2d-android,talenguyen/cocos2d-android,agenliuhuan/cocos2d-android