Cancel animation before destroying of SurfaceControl.

It can occur that access invalid SurfaceControl.
And this makes NullPointerException at runtime.

*** FATAL EXCEPTION IN SYSTEM PROCESS:android.anim.lf
java.lang.NullPointerException: mNativeObject is null.
    Have you called release() already?
  at android.view.SurfaceControl.checkNotReleased

We need to cancel animation before removing SurfaceControl

Bug: 150438558
Test: Existing tests pass.
      Open an app in freeform and maximize/restore it.
      Maximize freeform and press recent concurrently.

Change-Id: I95d319f66e0d571d270ed8295768bec6f1cbb0dd