Allow caller dismissing split to specify top stack

When starting a non-resizeable activity while in split-mode it is
important the non-resizeable activity causing the dismisal of the split
end up on top. This change allows the callers of dismiss split to
specify which stack will be topmost.

Fixes: 152943129
Test: atest testNonResizeableWhenAlreadyInSplitScreenPrimary testNonResizeableWhenAlreadyInSplitScreenSecondary
Change-Id: Iefba54183273f1d075fbeacdcd87133eb1f2e3ad

3 files changed, 11 insertions, 5 deletions

diff --git a/services/core/java/com/android/server/wm/ActivityStack.java b/services/core/java/com/android/server/wm/ActivityStack.java
index 78d2afc64f96..0f52248eb4dd 100644
--- a/services/core/java/com/android/server/wm/ActivityStack.java
+++ b/services/core/java/com/android/server/wm/ActivityStack.java
@@ -757,7 +757,7 @@ class ActivityStack extends Task {
                 // warning toast about it.
                 mAtmService.getTaskChangeNotificationController()
                         .notifyActivityDismissingDockedStack();
-                taskDisplayArea.onSplitScreenModeDismissed();
+                taskDisplayArea.onSplitScreenModeDismissed(this);
             }
         }
 
diff --git a/services/core/java/com/android/server/wm/ActivityStackSupervisor.java b/services/core/java/com/android/server/wm/ActivityStackSupervisor.java
index 1e5a924e1d4d..89cf6d44af77 100644
--- a/services/core/java/com/android/server/wm/ActivityStackSupervisor.java
+++ b/services/core/java/com/android/server/wm/ActivityStackSupervisor.java
@@ -2198,7 +2198,7 @@ public class ActivityStackSupervisor implements RecentTasks.Callbacks {
                 // split-screen in split-screen.
                 mService.getTaskChangeNotificationController()
                         .notifyActivityDismissingDockedStack();
-                taskDisplayArea.onSplitScreenModeDismissed();
+                taskDisplayArea.onSplitScreenModeDismissed(task.getStack());
                 taskDisplayArea.mDisplayContent.ensureActivitiesVisible(null, 0, PRESERVE_WINDOWS,
                         true /* notifyClients */);
             }
diff --git a/services/core/java/com/android/server/wm/TaskDisplayArea.java b/services/core/java/com/android/server/wm/TaskDisplayArea.java
index ec3c99bf0808..6016648236b3 100644
--- a/services/core/java/com/android/server/wm/TaskDisplayArea.java
+++ b/services/core/java/com/android/server/wm/TaskDisplayArea.java
@@ -1165,17 +1165,23 @@ final class TaskDisplayArea extends DisplayArea<ActivityStack> {
     }
 
     void onSplitScreenModeDismissed() {
+        onSplitScreenModeDismissed(null /* toTop */);
+    }
+
+    void onSplitScreenModeDismissed(ActivityStack toTop) {
         mAtmService.deferWindowLayout();
         try {
             mLaunchRootTask = null;
             moveSplitScreenTasksToFullScreen();
         } finally {
-            final ActivityStack topFullscreenStack =
-                    getTopStackInWindowingMode(WINDOWING_MODE_FULLSCREEN);
+            final ActivityStack topFullscreenStack = toTop != null
+                    ? toTop : getTopStackInWindowingMode(WINDOWING_MODE_FULLSCREEN);
             final ActivityStack homeStack = getOrCreateRootHomeTask();
-            if (topFullscreenStack != null && homeStack != null && !isTopStack(homeStack)) {
+            if (homeStack != null && ((topFullscreenStack != null && !isTopStack(homeStack))
+                    || toTop != null)) {
                 // Whenever split-screen is dismissed we want the home stack directly behind the
                 // current top fullscreen stack so it shows up when the top stack is finished.
+                // Or, if the caller specified a stack to be on top after split-screen is dismissed.
                 // TODO: Would be better to use ActivityDisplay.positionChildAt() for this, however
                 // ActivityDisplay doesn't have a direct controller to WM side yet. We can switch
                 // once we have that.