Don't return TYPE_RECENTS task in TopTaskTracker.getCachedTopTask

- We have no use-case to show TYPE_RECENTS (NexusLauncher or RecentsActivity) in Overview, stripping TYPE_RECENTS avoids accidentally showing RecentsAcitivty as a tile on swipe up

Fix: 355263037
Test: manually verify it doesn't break 3P Launcher; the bug itself cannot be verified as it cannot be easily reproduced
Flag: EXEMPT BUG_FIX
Change-Id: Id1b8e43dc7ddb9ad9c781b9a860fe4fba97d4be6
diff --git a/quickstep/src/com/android/quickstep/TopTaskTracker.java b/quickstep/src/com/android/quickstep/TopTaskTracker.java
index 3cf0542..23a1ec7 100644
--- a/quickstep/src/com/android/quickstep/TopTaskTracker.java
+++ b/quickstep/src/com/android/quickstep/TopTaskTracker.java
@@ -206,12 +206,17 @@
             Collections.addAll(mOrderedTaskList, tasks);
         }
 
-        // Strip the pinned task
         ArrayList<RunningTaskInfo> tasks = new ArrayList<>(mOrderedTaskList);
-        tasks.removeIf(t -> t.taskId == mPinnedTaskId);
+        // Strip the pinned task and recents task
+        tasks.removeIf(t -> t.taskId == mPinnedTaskId || isRecentsTask(t));
         return new CachedTaskInfo(tasks);
     }
 
+    private static boolean isRecentsTask(RunningTaskInfo task) {
+        return task != null && task.configuration.windowConfiguration
+                .getActivityType() == ACTIVITY_TYPE_RECENTS;
+    }
+
     /**
      * Class to provide information about a task which can be safely cached and do not change
      * during the lifecycle of the task.
@@ -267,8 +272,7 @@
         }
 
         public boolean isRecentsTask() {
-            return mTopTask != null && mTopTask.configuration.windowConfiguration
-                    .getActivityType() == ACTIVITY_TYPE_RECENTS;
+            return TopTaskTracker.isRecentsTask(mTopTask);
         }
 
         /**