Merge "Apply root task for launch activity animation." into udc-dev am:...

Merge "Apply root task for launch activity animation." into udc-dev am: 181bcdba am: e2cdba05 am: 9ab1e19a am: d14e3019

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23109637



Change-Id: I9c5201b93abf9714817caca78f2fc3eef326a261
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>