From 2a5c839dad8fce78cdd6ea93d37f1607f29a33da Mon Sep 17 00:00:00 2001
From: Martijn Coenen <maco@google.com>
Date: Mon, 1 Oct 2018 10:17:06 +0200
Subject: [PATCH] Fix getDefaultDisplayHomeActivityForUser.

And check for null HomeActivity record, To fix NullPointerException
in ActivityManagerService.

Bug: 116875894
Test: builds
Change-Id: I543c235011bf668e0b1bfbc4252a41c49490ac27
---
 .../com/android/server/wm/ActivityStackSupervisor.java     | 3 +--
 .../com/android/server/wm/ActivityTaskManagerService.java  | 7 +++++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/services/core/java/com/android/server/wm/ActivityStackSupervisor.java b/services/core/java/com/android/server/wm/ActivityStackSupervisor.java
index 77b331e6c4a9c..f040dd41002be 100644
--- a/services/core/java/com/android/server/wm/ActivityStackSupervisor.java
+++ b/services/core/java/com/android/server/wm/ActivityStackSupervisor.java
@@ -2611,8 +2611,7 @@ public class ActivityStackSupervisor extends ConfigurationContainer implements D
     }
 
     ActivityRecord getDefaultDisplayHomeActivityForUser(int userId) {
-        getActivityDisplay(DEFAULT_DISPLAY).getHomeActivityForUser(userId);
-        return null;
+        return getActivityDisplay(DEFAULT_DISPLAY).getHomeActivityForUser(userId);
     }
 
     void resizeStackLocked(ActivityStack stack, Rect bounds, Rect tempTaskBounds,
diff --git a/services/core/java/com/android/server/wm/ActivityTaskManagerService.java b/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
index 3ede8bc818e08..195f0485117ed 100644
--- a/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
+++ b/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
@@ -6296,8 +6296,11 @@ public class ActivityTaskManagerService extends IActivityTaskManager.Stub {
                             FLAG_ACTIVITY_TASK_ON_HOME);
                     ActivityOptions activityOptions = options != null
                             ? new ActivityOptions(options) : ActivityOptions.makeBasic();
-                    activityOptions.setLaunchTaskId(
-                            mStackSupervisor.getDefaultDisplayHomeActivity().getTask().taskId);
+                    final ActivityRecord homeActivity =
+                            mStackSupervisor.getDefaultDisplayHomeActivity();
+                    if (homeActivity != null) {
+                        activityOptions.setLaunchTaskId(homeActivity.getTask().taskId);
+                    }
                     mContext.startActivityAsUser(intent, activityOptions.toBundle(),
                             UserHandle.CURRENT);
                 } finally {