Remove SurfaceFreezer leash when unfreeze

Before, after unfreeze, the leash will not be removed until its parent
is gone, which may stay for a while. Now, it should be cleaned up
immediately.

Bug: 196173550
Test: test with demo app with ag/15559306
Change-Id: Ie21019bddbdaa6fddc351d07cc372f621ae5176e

services/core/java/com/android/server/wm/SurfaceFreezer.java

@@ -117,7 +117,7 @@ class SurfaceFreezer {
         SurfaceControl leash = mLeash;
         mLeash = null;
         final boolean scheduleAnim = SurfaceAnimator.removeLeash(t, mAnimatable, leash,
-                false /* destroy */);
+                true /* destroy */);
         if (scheduleAnim) {
             mWmService.scheduleAnimationLocked();
         }