Integrate split pair cold launch transition with shell transition

Separate RemoteAnimationTargetCompat.wrap to wrapApps and wrapNonApps to
support extracting non-app targets. Update to distinguish a divider
change from non-app targets to ensure it can be animated properly.

Fix: 222163803
Test: atest RemoteTransitionTest
Test: atest SplitTransitionTests
Test: enabled shell transition, cold launch a split pair from overview
      has proper transition.
Change-Id: Ibd45d612e75c3a3b664aaf3944f424289419858b