Merge "Avoid double end on PipTransitionAnimator" into udc-dev am: 839aca67 am: 3f0adff4

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23270226



Change-Id: I3a12a4ecf5aa00ea864105131f7b34970fcd5295
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>