Add AndroidX SpringAnimation library to core.

This allows core libraries (such as predictive back progress animation)
to use spring animation.

Files in androidx/dynamicanimation/animation that are not copied over:

FlingAnimation.java - Unused atm
AnimationHandler.java - Replaced with the framework AnimationHandler
FloatPropertyCompat.java - Replaced with FloatProperty
FrameCallbackScheduler.java - Unused in framework AnimationHandler

Test: m -j
Bug: 238475284
Change-Id: Ifdf847da0aa2a6cf57e18f9ac7c91bb0fe3b12c2