Fix NotificationGuts tests

- NPE’s ‘cause there was no interaction listener set in the tests, added
  this to test set up
- Failures with saving importance because closeControls no longer saves
  any changes, it just closes the controls now. Updated those tests to
  use saveImportance instead.
- Removed the test ensuring that closeControls wouldn’t save importance
  if it was passed save = false, since closeControls no longer does that.

Test: NotificationGuts tests no longer fail (runtest systemui)
Change-Id: I3251f4f379654f4cc9eb3a506b722e515c6fe971