Add null check when logging quick switch

Test: none
Fixes: 209993127
Change-Id: I927f8969cf5ef3759b501fe1ada4d3b061b53d06
diff --git a/quickstep/src/com/android/quickstep/views/TaskView.java b/quickstep/src/com/android/quickstep/views/TaskView.java
index 9887630..6a2c997 100644
--- a/quickstep/src/com/android/quickstep/views/TaskView.java
+++ b/quickstep/src/com/android/quickstep/views/TaskView.java
@@ -470,7 +470,9 @@
         stubInfo.user = componentKey.user;
         stubInfo.intent = new Intent().setComponent(componentKey.componentName);
         stubInfo.title = task.title;
-        stubInfo.screenId = getRecentsView().indexOfChild(this);
+        if (getRecentsView() != null) {
+            stubInfo.screenId = getRecentsView().indexOfChild(this);
+        }
         return stubInfo;
     }