Merge "Add activity option flag for background starts for bubbles" into udc-dev am: 0dcaf197

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21686310



Change-Id: I1e200083f65a43f47d25c372e46e399e6cac53a2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>