Add Transition.canOverscroll()

This method is used to understand if any transformations have been
defined in the overscroll spec and therefore if we can perform the
overscroll gesture.

Test: Just a refactor
Bug: 336710600
Flag: com.android.systemui.scene_container
Change-Id: Ife8ede54a6db6d01c53e19b1b1f8d287fbb09f44
2 files changed