Handle text animation in different display situations.

Bug: 31623549

Test: Manually pull down animation in 4 situations.

Create different controllers to handle when display
-Is empty
-Has input and quick result
-Has input but no quick result
-Is only displaying the result

Start using reverseLayout instead of stackFromEnd (had issues).

Change-Id: I72de7f22f8eda035ef82edeb44b57c06acc1be95