Remove UseCounter

sky/engine/core/frame/LocalDOMWindow.cpp

Index: sky/engine/core/frame/LocalDOMWindow.cpp
diff --git a/sky/engine/core/frame/LocalDOMWindow.cpp b/sky/engine/core/frame/LocalDOMWindow.cpp
index d765b0e7541368a05c2b183dbf63bafe0e41efa2..0e7557a45e8423dc58858425af8249cee458b2e7 100644
--- a/sky/engine/core/frame/LocalDOMWindow.cpp
+++ b/sky/engine/core/frame/LocalDOMWindow.cpp
@@ -690,10 +690,9 @@ bool LocalDOMWindow::addEventListener(const AtomicString& eventType, PassRefPtr<
 
     lifecycleNotifier().notifyAddEventListener(this, eventType);
 
-    if (eventType == EventTypeNames::unload) {
-        UseCounter::count(document(), UseCounter::DocumentUnloadRegistered);
+    if (eventType == EventTypeNames::unload)
         addUnloadEventListener(this);
-    }
+
     return true;
 }