Refactor #3878 #3922 #3963 #3983: Put temporary proto variable in window
Merge branch 'develop-3.0' of https://github.com/cocos2d/cocos2d-html5 into develop-3.0

# Via dingpinglv
* 'develop-3.0' of https://github.com/cocos2d/cocos2d-html5:
Merge pull request #1556 from pandamicro/develop-3.0

Refactor #3878 #3922 #3963 #3983: Put temporary proto variable in window