Handle task visibility change to show the surface

- When a new task organizer is registered, while a task is invisible,
  onTaskAppeared() may get called with isVisible=false.
- Later on when visibility becomes true, onTaskAppeared() is not called
  and hence that surface would still remain hidden.
- Handle this scenario in onTaskInfoChanged to make sure surface is
  shown correctly.

Fix: 272296051
Test: Tested manually by triggering this case on gcar_ui_portrait
Change-Id: Ie61be170ae92dac1c4eab102e76629f989afa64c