Fix an issue with visibility of the BubbleBarLayerView

We don't need this isStackExpanded check here, instead if we have
bubbles & are unlocked, we should set the view as visible.

Flag: WM_BUBBLE_BAR
Test: manual - enable bubbles, get a bubble, lock the screen
             - unlock the screen
             - swipe up on handle to show bubbles, ensure the bubble
               expanded view is visible
Bug: 279032445
Change-Id: I143df78cf8b618cff1d3af2d479aa1996d611936