issue #2770: fix some warning
issue #2770: fix some warning
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-x into iss2770_fix_warnings
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-x into iss2770_fix_warnings
issue #2770: fix some warning
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-x into iss2770_fix_warnings
Merge pull request #4206 from boyu0/iss2770_fix_warnings

[ci skip]issue #2770: fix warnings