Make Animators pass internal tests

Fixes: 269524599

AnimatorSet wasn't properly managing cloning and
ViewPropertyAnimatorTest didn't work when the animator took too
long to start. This CL fixes both problems.

Test: ran animation tests
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:9cbebf9fb2066cf8765ba794a9181c6e6fca2ca4)
Merged-In: Icdf2e9d75d93fa6a4e99833c24a40b48b051f568
Change-Id: Icdf2e9d75d93fa6a4e99833c24a40b48b051f568