Update group suppression for bubbles

When bubbles are opened or the notification for the bubble is dismissed
the group needs to be updated to factor in the new "count" of items in
that group.

* BubbleController notifies NotificationGroupManager to update suppression
  whenever a bubble is selected (i.e. notification for that bubble is
  hidden from shade)
* NotificationGroupManager checks if the children for a group are being
  suppressed from the shade due to bubbles, and factors that into whether
  the summary should be suppressed.
* BubbleController listens for group suppression changes to remove
  suppression in the case that you had a group, swiped the group away,
  and then more children were added to that group -- the summary should
  come back

Test: manual
   Open bubbles
   1) post a group of bubbles
   2) expand the stack and tap through each, after each tap check that
      the # of notifs in the group go down until the group is hidden

   Swipe & add bubble
   1) post a group of bubbles
   2) swipe the group away in the shade
   3) add the group again => note that the group appears in shade

Bug: 130250809
Change-Id: I3cfcdcbb0d9d17c51e2e5886e4f7e31a522b9085