Enable running-task callbacks for Desktop Windowing.

- Enable RecentTasksListener (sending updates from Shell to Launcher)
  if Desktop Mode and Flag.enableDesktopWindowingTaskbarRunningApps
  are enabled.
- Add a method onRunningTaskChanged(RunningTaskInfo) to
  RecentTasksListener to be able to update the Taskbar when a Task
  changes windowing mode.

Bug: 332504528
Test: RecentTasksControllerTest
Change-Id: I1cd9d5767b43fb44498ef8718655fcb770d9cbfb