Add basic home to recents anim for fallback recents

For users/OEMs who ship with a different default launcher, we should
provide at least a basic animation from home to recents. This creates a
simple cross-fade animation if coming from a separate home activity.

Bug: 132449252
Test: Have different default launcher, go to home, go to recents
Change-Id: I5ac7b0eedbcdf1e020c31d9cf120887a4bb3826a