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

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



Change-Id: Ied277490ef71863f7fcadd9fb650d5adb62a1c9e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>