Nuke mActivitiesWaitingForVisibleActivity

Instead of relying on this brittle architecture we just check
whether the animation has finished. Much cleaner now :-)

Test: Swipe up to recents from Chrome, relaunch in the right
moment. Observe no jumpcut.
Test: Existing lifecycle tests should cover this
Test: android.server.am.lifecycle: All passed!
Bug: 111227410
Change-Id: I83b3dc0e026e842bf260a376ce9a57afd1b01d9f
diff --git a/services/core/java/com/android/server/wm/AppWindowToken.java b/services/core/java/com/android/server/wm/AppWindowToken.java
index 78199d44..220370c 100644
--- a/services/core/java/com/android/server/wm/AppWindowToken.java
+++ b/services/core/java/com/android/server/wm/AppWindowToken.java
@@ -2784,6 +2784,8 @@
 
         getDisplayContent().mAppTransition.notifyAppTransitionFinishedLocked(token);
         scheduleAnimation();
+
+        mActivityRecord.onAnimationFinished();
     }
 
     @Override