Merge "ActivityView animations!" into rvc-dev am: ab0ffd1d48 am: 61d58dcf0a am: bfb7eecd68

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11793537

Change-Id: I8c4ffa269f4b4e41d0fa475831a088199cd1258f