Merge "Use new onStartSplitLegacy when starting split from overview" into...

Merge "Use new onStartSplitLegacy when starting split from overview" into tm-dev am: 8aead550 am: e17589f4 am: eb47b22c am: 9fb55d55

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/17779173



Change-Id: Ia9bcc89d4f275bad975f88a7627ca3691645aca2
Ignore-AOSP-First: this is an automerge
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>