cocos2d/cocos2d-x — pull request #6491 by cocosQA (2014-04-28 08:19:27+00:00)
Title: [ci skip]Clear error message buffer before request.

In the below case,

1. 1st request. It was finished with error message.
1. 2nd reqeust. It has no error message.

after 2nd request, this buffer sill had 1st error.