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: f06f6e7f am: a36b69f8

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



Change-Id: I85cfd3c84254b47b592c68cff25d77964bf12e25
Ignore-AOSP-First: this is an automerge
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>