Fixed the problem where AlertActivity may not show newer past events

The selection arg was in a static so it wasn't updated.
I also reverted the order to before so people won't get confused.
We do the same in Agenda anyways.
We automatically scroll to the bottom so people will always see the newest ones at the bottom anyways.

Change-Id: I266a292a9d1f7cb641273e573adc6c4d996c0028