Null mRecentsAnimationController in the end

Fixes: 186141367
Test: manual
Change-Id: Iccc96ef6ffebcb0b7a7953d2423dfdb738823431
diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index e4fa1aa..36ba93b 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -3069,7 +3069,6 @@
         }
 
         mRecentsAnimationController.finish(toRecents, () -> {
-            mRecentsAnimationController = null;
             if (onFinishComplete != null) {
                 onFinishComplete.run();
             }
@@ -3079,6 +3078,7 @@
             // typical example of this is (1) user swipes up from app to Overview (2) user
             // taps on QSB (3) user goes back to Overview and launch the most recent task.
             setCurrentTask(-1);
+            mRecentsAnimationController = null;
         });
     }