Limit the suggestions to be shown to 5.

- when creating the dashboard data, pass the sublist of suggestions to
cap the total number of suggestions to be shown to 5.
- if user swipe away the suggestion, it will only remove the suggestion
from the suggestion adapater, and will not trigger rebuilding the whole
UI.

Change-Id: I3bbc08bb67c411ff5671a837efa40da0ac885983
Merged-In: I1efabeb2a805c670007c631d3ccb0fdfbde7b55a
Fix: 64072051
Test: make RunSettingsRoboTests