Handle non-visually-interruptive updates better in bubbles

1) If its a non-visual update to an existing bubble don't
   alter the bubble order or show a flyout
2) If its a non-visual update to a bubble in the overflow
   don't promote that content out of the overflow

Test: BubbleControllerTest
Bug: 162975422
Bug: 163608157
Change-Id: I6d8e67028a5aacf1a23acdbfaeb0fa8a50f829a6
5 files changed