Fix bubble tx when the bar is collapsed

The previous behavior positioned the second bubble correctly but all
other bubbles behind the second bubble.

Flag: com.android.wm.shell.enable_bubble_bar
Fixes: 366254467
Test: manual
       - create multiple bubbles in the bubble bar
       - expand and collapse the bubble bar and observe bubbles
         move correctly from right to left when expanding and from
         left to right when collapsing
Change-Id: I1db6daf629826af8d079a27d582e0c7e89fe2289