Merge "Determine whether to support activities in multi window (4/n)" into sc-dev am: 314e0d14 am: fe0779fe am: 3053ff17

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14404373

Change-Id: I02f51fb210e95610659fcbc01e1396e13a857569