Remove some methods in animation helper & use from bubble positioner

1 - Some of the positioning logic in BubbleBarAnimationHelper could rely
on existing methods in BubblePositioner, so migrate to those.

2 - Create a general method to retrieve the resting bounds of the
expanded view for either floating / bubble bar

3 - Use the new method on bubble positioner for retrieving bounds info
in BubbleTransitions -- this will help remove the reliance on layerView.

Flag: com.android.wm.shell.enable_create_any_bubble
Test: atest BubblePositionerTest BubbleTransitionsTest
Test: manual - turn on enable_bubble_to_fullscreen and observe the
               transitions: drag app handle to bubble, use app handle
               menu to bubble, drag bubble to fullscreen, use bubble
               menu to fullscreen
Bug: 408453889
Change-Id: If86ec86ee2b7e1057cdf25ec77b0cf10f96d20c9