Issue #4277: move gl's constant variable to cc
Merge branch 'develop-3.0' of https://github.com/cocos2d/cocos2d-html5 into Iss3427_NewEventDispatcher
Merge pull request #1638 from dingpinglv/Iss4277_FixBugsForV3.0

Issue #4277: move gl's constant variable to cc