Remove the flag isCarouselInTransition

The clock vertical shift issue when onTimeTick is resolved.
We no longer need to inspect if we are scrolling the carousel.

1. Remove isCarouselInTransition. It's not really idea to create a state
   in a view and reference it externally. The view should be as
   stateless as possible.
2. Remove onTimeTick when populating, since this looks weird when we
   have second level clocks that the second arm moves every time when
   populateing

Test: Manually tested time tick does not make clock view vertically
      shift
Bug: 278850684
Change-Id: I6478a4467f7d9e3091a709a5978a042fa65d3d3b