Fix getDefaultDisplayHomeActivityForUser.

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

Bug: 116875894
Test: builds
Change-Id: I543c235011bf668e0b1bfbc4252a41c49490ac27

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 77b331e6c4a9..f040dd41002b 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 3ede8bc818e0..195f0485117e 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 {