fixed ui header file include problem
Merge pull request #6868 from andyque/fixInclude

fixed ui header file include problem
adding guard for the callback condition
Merge pull request #6869 from visiblelight/texturecache

adding guard for the callback condition in `TextureCache::addImageAsyncCallBack`
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into HEAD