Make TaskStackTransitionObserver...

- Update tasks moved to front on all tasks rather than just freeform
- Do the updates onTransitionReady so that the launcher is updated
  before the animation plays.

Fix: 369975365
Fix: 356619247
Test: atest TaskStackTransitionObserverTest
Flag: com.android.window.flags.enable_task_stack_observer_in_shell

Change-Id: I08404b2dfbd42169f0be33c4f7c7b7d53ee6aa11