Add animation override support to AE

1. Add endParentSize to Change - It's necessary to calculate overlay Change transition.
2. Add support to obtain custom animation from Change's AnimationOptions
3. Respect the shouldShowBackdrop value if there's an override from
   AnimationOptions

Bug: 295805497
Test: atest WMShellUnitTests
Flag: com.android.window.flags.activity_embedding_overlay_presentation_flag
Flag: com.android.window.flags.move_animation_options_to_change

Change-Id: I0799947a1e468c426945f77ce8d969cfb81a0d58