Allow starting split from home, selecting second app from overview

* KI: After entering overview, swiping to exit doesn't
clear split state. That's because LauncherRecentsView#reset()
gets called both when entering and exiting overview.
We'd need to check or pass through what state we're moving to
to determine whether or not actually to reset state in
SplitSelectStateController, or handle that at the gesture level

Flag: ENABLE_SPLIT_FROM_WORKSPACE_TO_WORKSPACE
Test: Manual, split paths work w/ and w/o flag enabled
Bug: 276361926
Change-Id: I39391ac5f92b774d8198930829caabe84d950598