Merge "Separate code paths to launch split from existing pair vs new pair" into udc-dev am: 258019fe8e am: 1f27273c06

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/23320818

Change-Id: I11104b119109468f3b0984fb670b6196c418b97d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>