Android: am instrument proto test result architecture review

I don’t know how code review is implemented in Google for the changes (f0c7198 and 50307d9) that will be reviewed here. I also can’t see the issue tracker for the particular problem that was being fixed. But since I’m affected by this change, I can only make this a public thing and hope for the best. If you don’t like to discuss or know about problems, read no further.

Disclaimer: I am in no way attacking Google or its employees. Everything expressed below are my personal opinions.