[rotang] OOO not working properly with Outage larger than a shift.

- Turns out the Personal Outage logic was checking for an outage to start
or end inside a day. This gave that longer outages larger than a full shift
was not handled correctly.
- While there I moved the Generator code over to the shared handlers rota method too.


Bug: 845549
Change-Id: Idf6ebb4884749797314095f3eab9c31e40d53d4e
Reviewed-on: https://chromium-review.googlesource.com/c/1365290
Reviewed-by: Tiffany Zhang <zhangtiff@chromium.org>
Commit-Queue: Ola Karlsson <olakar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#19393}