Allow the embedder to disable the Notification constructor.

Source/modules/notifications/Notification.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 22 matching lines @@
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/dom/ExecutionContextTask.h"
 #include "core/dom/ScopedWindowFocusAllowedIndicator.h"
 #include "core/events/Event.h"
 #include "core/frame/UseCounter.h"
 #include "modules/notifications/NotificationOptions.h"
 #include "modules/notifications/NotificationPermissionClient.h"
+#include "platform/RuntimeEnabledFeatures.h"
 #include "platform/UserGestureIndicator.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebSerializedOrigin.h"
 #include "public/platform/modules/notifications/WebNotificationData.h"
 #include "public/platform/modules/notifications/WebNotificationManager.h"
 
 namespace blink {
 namespace {
 
 WebNotificationManager* notificationManager()
 {
     return Platform::current()->notificationManager();
 }
 
 } // namespace
 
-Notification* Notification::create(ExecutionContext* context, const String& title, const NotificationOptions& options)
+Notification* Notification::create(ExecutionContext* context, const String& title, const NotificationOptions& options, ExceptionState& exceptionState)
 {
+    // The Web Notification constructor may be disabled through a runtime feature. The
+    // behavior of the constructor is changing, but not completely agreed upon yet.
+    if (!RuntimeEnabledFeatures::notificationConstructorEnabled()) {
+        exceptionState.throwTypeError("Illegal constructor. Use ServiceWorkerRegistration.showNotification() instead.");
+        return nullptr;
+    }
+
     Notification* notification = new Notification(title, context);
 
     notification->setBody(options.body());
     notification->setTag(options.tag());
     notification->setLang(options.lang());
     notification->setDir(options.dir());
     if (options.hasIcon()) {
         KURL iconUrl = options.icon().isEmpty() ? KURL() : context->completeURL(options.icon());
         if (!iconUrl.isEmpty() && iconUrl.isValid())
             notification->setIconUrl(iconUrl);
@@ skipping 180 matching lines @@
     return m_state == NotificationStateShowing || m_asyncRunner.isActive();
 }
 
 void Notification::trace(Visitor* visitor)
 {
     RefCountedGarbageCollectedEventTargetWithInlineData<Notification>::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 } // namespace blink