Merge "Implement splitting from Taskbar long-press" into tm-dev am: e15927eec7

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/17530994

Change-Id: I5b5f021a823266771d99a294863f7005e4cb925e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>