Disallow constructing the Notification object in a Service Worker.

Source/modules/notifications/Notification.cpp

Index: Source/modules/notifications/Notification.cpp
diff --git a/Source/modules/notifications/Notification.cpp b/Source/modules/notifications/Notification.cpp
index 4fbf7eb9b9f1481742549890101193ebfc5d26f2..f61571ffe22da3888280c12f1075650bf822ca5f 100644
--- a/Source/modules/notifications/Notification.cpp
+++ b/Source/modules/notifications/Notification.cpp
@@ -66,6 +66,12 @@ Notification* Notification::create(ExecutionContext* context, const String& titl
         return nullptr;
     }
 
+    // The Web Notification constructor may not be used in Service Worker contexts.
+    if (context->isServiceWorkerGlobalScope()) {
+        exceptionState.throwTypeError("Illegal constructor.");
+        return nullptr;
+    }
+
     Notification* notification = new Notification(title, context);
 
     notification->setBody(options.body());