Merge "Only add 2nd screen by default for split display" into sc-v2-dev am: cceef46f16 am: 42a79a3023

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/15583057

Change-Id: Id04adff0053d16681aa4a9015fb70fc57ac52641