Fix display of upcoming events in the LOP widget.

#6004 

This PR fixes display of events in the LOP widget when sorted by event dates. 

On the left we have a widget based on os_sv_list. On the right it's a view based on the "calendar/upcoming".
On 12:28 we see the event on the left:
![selection_311](https://cloud.githubusercontent.com/assets/4497748/3465725/1dac8d16-026e-11e4-842d-7193e0726df4.png)

Changing the event start time to an earlier time we see the event is gone (started more than 30 minutes ago):
![selection_312](https://cloud.githubusercontent.com/assets/4497748/3465726/1daf1f4a-026e-11e4-8d83-86c6c105f912.png)

Tested on hwpi db.