Use all targets passed back for recents animation

* Previously we were removing all targets except for
the app that was to be animated. That caused issues
because we look for the home app to determine if the
app leashes need to be drawn underneath or not.
* Now (assuming at most two non-home app leashes will
be sent) we add all the non-home targets along with
the desired app target by excluding 1 of the 2 non-home
apps

Bug: 199936292
Change-Id: I252d6c663e9ca145ef394ac08d9a32da02d4a03b