Merge pull request #4969 from dumganhar/develop

Updates JS-Test submodule.
long —> ssize_t for some classes.
Adds override keyword.
fix for jsval_to_ssize and ssize_to_jsval, it only supports 32 bits now. Otherwise, (string).toFixed(0) will fails. Do we need 64 bit for JS?
Merge branch 'develop' of git://github.com/cocos2d/cocos2d-x into develop