Merge "Only need to dismiss stage if one of the task is closed." into udc-dev am: 54d018e1de

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22779458

Change-Id: I793feed9d30b2ae7ccb46470399261c1d12ea0fa
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
index ceef373..cca63ef 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
@@ -2419,12 +2419,13 @@
                     }
                 }
             }
-            // If the size of dismissStages > 0, the task is closed without prepare pending
+            // If the size of dismissStages == 1, one of the task is closed without prepare pending
             // transition, which could happen if all activities were finished after finish top
             // activity in a task, so the trigger task is null when handleRequest.
+            // Note if the size of dismissStages == 2, it's starting a new task, so don't handle it.
             final ArraySet<StageTaskListener> dismissStages = record.getShouldDismissedStage();
             if (mMainStage.getChildCount() == 0 || mSideStage.getChildCount() == 0
-                    || dismissStages.size() > 0) {
+                    || dismissStages.size() == 1) {
                 Log.e(TAG, "Somehow removed the last task in a stage outside of a proper "
                         + "transition.");
                 final WindowContainerTransaction wct = new WindowContainerTransaction();