Move ScreenRotationAnimation to DisplayContent

Move the reference to the ScreenRotationAnimation from WindowAnimator to
DisplayContent now that the animation runs on the
SurfaceAnimationRunner.

Next step is to delete the DisplayContentsAnimator class in
WindowAnimator.

Bug: 131727512
Test: WmTests
Change-Id: I7c9994eebcf95ae0f329c65e39832c18f025101d
6 files changed