Merge "Remove legacy activity starter code" into udc-dev am: 2222c55f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22976334



Change-Id: I7c7e6b2b32d5625b44afd2a7abfad0ea43a6c18b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>