Don't bubble things when we shouldn't

I haven't been able to repro these issues outside of tests on
cuttlefish, but I think logically these fixes make sense & seem to
resolve the test issue.

- Ensure non-notifying updates to bubbles in the overflow don't
  clobber the FLAG_BUBBLE state
- onRankingUpdate should only bubble stuff up if it's not active and
  not in the overflow (previously just not active)

Bug: 238896626
Test: atest BubblesTest#testNonInterruptiveUpdate_doesntOverrideOverflowFlagBubble
Test: atest --no-bazel-mode --iterations 20 PlatformScenarioTests:android.platform.test.scenario.sysui.bubble.ExpandAndDragToDismissTest
      (with vadim's changes & another CL)
Change-Id: Id588c1130e62533a23dc931dfb4fe3c92125a905