Use translation to move bubble bar during bubble drag

Revert logic to set translation on each BubbleView and background.
Background translation was set with bounds offset and BubbleView was
using setTranslationX(). This made it hard to synchronise background and
child view translations. And led to flickers.

Applying translation on the BubbleBarView itself, but applying the
reverse of the translation to the dragged BubbleView. This ensures that
the dragged bubble position is not affected by the parent translation.

Introducing a new property for BubbleView that is used to apply
translation during drag. It takes into account the offset of the
BubbleBarView.

Bug: 330585402
Flag: ACONFIG com.android.wm.shell.enable_bubble_bar DEVELOPMENT
Test: drag bubble to other side and release before the bubble bar
  animation finishes, observe no flickers
Test: drag expanded view to other side and release before the bar
  animation finishes, observe no flickers
Change-Id: I1712ed6ac26831f10466dbaf0378f8aabb29629d