Skip adding tasks to the skip list if they won't be processed

Bug: 199523354
Test: atest TaskSnapshotControllerTest
Change-Id: Ibb94dac74da8adbc0fedd3ca8be26b6b027417d1

services/core/java/com/android/server/wm/TaskSnapshotController.java

@@ -168,6 +168,9 @@ class TaskSnapshotController {
      */
     @VisibleForTesting
     void addSkipClosingAppSnapshotTasks(ArraySet<Task> tasks) {
+        if (shouldDisableSnapshots()) {
+            return;
+        }
         mSkipClosingAppSnapshotTasks.addAll(tasks);
     }