Implement new dismissal behaviour of contextual card

Currently, if a contextual card gets dismissed, it will be gone forever.
After this change, all cards being dismissed can be shown again after a
certain amount of time(e.g one day). In order to calculate the amount of
time, CARD_DISMISSED column is replaced with DISMISSED_TIMESTAMP. Once a
card gets dismissed, a timestamp will be recorded for a corresponding
card.

In this change, some methods are moved from CardDatabaseHelper to
ContextualCardFeatureProvider. So OEMs could replace the providers with
their own ones to get cards and have different dismissal behaviours.

Bug: 143055685
Test: rototests
Change-Id: I00ace98991cabcbfcae4fc47a44e9448683d680c