Only override ActivityEmbedding animation for embedded activities

Before, we check if there is any split rule meeting the bounds
requirement for the given Task bounds in order to determine whether or
not to override the animation.

This can cause issue when the apps later unregister the split rules
while there is existing split. Also, this is hard to determine as we now
have SplitAttributesCalculator which can change the split state for the
same bounds.

To fix these problem, we now check if the app transition contains any
embedded activity (embedded TaskFragment that is not filling Task), to
determine if the animation should be played by the organizer.

Fix: 242051445
Test: atest WmTests:AppTransitionControllerTest
Change-Id: Ie90ba085cab3d4072f47cc3599d0494324fa39a9