The Object.defineProerty shim had a bogus check for browser implementation and this change fixes it.
Merge pull request #997 from oupengsoftware/taskbranch/COCOS2D-47

The Object.defineProerty shim had a bogus check for browser implementation and this change fixes it.
use native splice function for ArrayAppendObjectToIndex,ArrayAppendObjectsToIndex
Merge branch 'develop' of github.com:cocos2d/cocos2d-html5 into develop