Merge "Start tracking unknownvisibility immediately for launchBehind" into udc-dev am: 440cf522

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23089553



Change-Id: I4fa1de0701d2d755c56ffe2a9aae2419569b505a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>