Merge "Improve enter and dismiss transition by using snapshot" into udc-dev...

Merge "Improve enter and dismiss transition by using snapshot" into udc-dev am: 472c42cc am: 8b8314f1

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23258461



Change-Id: I0a0a37c9b6abc643102121e9d3335f50bf73d1b2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>