Merge "Fix the activity enter / exit animation." into udc-dev am: 0209aeede5

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22778356

Change-Id: I3b9c87235101f0cfc8fc42e71fdeaa79f6797ffe
Signed-off-by: Automerger Merge Worker <[email protected]>