Making sure the reorder animation goes back to the initial position.

The animation ReorderPreviewAnimation handles two animations, one when
the mode is MODE_HINT and the other MODE_PREVIEW. The animation is
basically the same but MODE_PREVIEW ocilates to finalDelta and back
to initDelta. MODE_HINT stays in finalDelta. When finish, we have to
go back to the initial position.

This behaviour is currently done using logic, making sure the view stays
in finalDelta no matter the value of the animation, the bug is in this
logic. I think is better to do this with the current animation API by
setting setRepeatCount to 0 on the HINT case and reverting the animation
when finish so it goes back to the initial position.

This seems to have been there for a long time, at least since the
creating of git_main, but it became more aparent now. In a follow up cl
I will move this class to it's own file and into kotlin to help if there
are issues here again.

Fix: 294473336
Test: manual testing
Flag: NA
Change-Id: I4ac5de3ce8a8170944a072c6ce41c65d0963a780