I think you are misunderstanding the function. This is preserving the behavior that Ian implemented here: https://github.com/mozilla-b2g/gaia/blob/ce8dc3feceb9060de1e347a2641ce348f6d5fa6a/apps/clock/js/onring.js#L47-L68 . I wasn't able to replicate the behavior that Ian is referring to, but it seemed unwise to change this without being able to duplicate the issue and verify that the workaround is unnecessary. For that reason, ```isVisibleWorkaround``` attempts to use the same setTimeout method as in the original code. 

To that end, I think this is implemented correctly. If you would like, I can file another bug and ask Ian for guidance on this.