From f45df50bdb5c0979c481737c810cc2deaee8c278 Mon Sep 17 00:00:00 2001
From: Tim Murray <timmurray@google.com>
Date: Tue, 13 Dec 2022 16:04:55 -0800
Subject: [PATCH] ActivityTaskManagerService: clear previous if it becomes
 topApp

The same app shouldn't be top and previous. When topApp changes, if
the same app is previous, clear previous.

Test: atest WmTests:WindowStateTests
Bug: 262213347

Change-Id: Ia0e3fd2adf1c9c16e8d24b89785d6cd33f74d962
---
 .../java/com/android/server/wm/ActivityTaskManagerService.java   | 1 +
 1 file changed, 1 insertion(+)

diff --git a/services/core/java/com/android/server/wm/ActivityTaskManagerService.java b/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
index e475eb6e992c0..937f2f1c1a2e2 100644
--- a/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
+++ b/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
@@ -4841,6 +4841,7 @@ public class ActivityTaskManagerService extends IActivityTaskManager.Stub {
                 // If there is no resumed activity, it will choose the pausing or focused activity.
                 : mRootWindowContainer.getTopResumedActivity();
         mTopApp = top != null ? top.app : null;
+        if (mTopApp == mPreviousProcess) mPreviousProcess = null;
     }
 
     /**