This reverts commit 02301df216
and 65d2171d00.
Dropped addition of new API because androidx's FragmentManagerImpl now
employs a workaround that removes the necessity to reflect into
mListener and doesn't need add/removeAnimationListener either.
Bug: 117519981
Test: atest AnimationTest
Change-Id: I7250570190f40f6c5da8ef65ed81b2d4bb815cf5