Merge "Move transition utility functions into shell.util" into udc-dev am:...

Merge "Move transition utility functions into shell.util" into udc-dev am: d3d32373 am: d2ceb668

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21529517



Change-Id: Iaa91eb0c22ab247d11eb746c0602f1e21586f909
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>