Add blink-side plumbing for ServiceWorker -> Document postMessage (1/3)

Source/modules/serviceworkers/NavigatorServiceWorker.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/serviceworkers/NavigatorServiceWorker.h"
 
+#include "core/dom/Document.h"
 #include "core/frame/DOMWindow.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Navigator.h"
 #include "modules/serviceworkers/ServiceWorkerContainer.h"
 
 namespace WebCore {
 
 NavigatorServiceWorker::NavigatorServiceWorker(Navigator& navigator)
     : DOMWindowProperty(navigator.frame())
 {
 }
 
 NavigatorServiceWorker::~NavigatorServiceWorker()
 {
 }
 
+NavigatorServiceWorker* NavigatorServiceWorker::from(Document& document)
+{
+    if (!document.frame() || !document.frame()->domWindow())
+        return 0;
+    Navigator& navigator = document.frame()->domWindow()->navigator();
+    return &from(navigator);
+}
+
 NavigatorServiceWorker& NavigatorServiceWorker::from(Navigator& navigator)
 {
     NavigatorServiceWorker* supplement = toNavigatorServiceWorker(navigator);
     if (!supplement) {
         supplement = new NavigatorServiceWorker(navigator);
         provideTo(navigator, supplementName(), adoptPtrWillBeNoop(supplement));
+        // Initialize ServiceWorkerContainer too.
+        supplement->serviceWorker();
     }
     return *supplement;
 }
 
 NavigatorServiceWorker* NavigatorServiceWorker::toNavigatorServiceWorker(Navigator& navigator)
 {
     return static_cast<NavigatorServiceWorker*>(WillBeHeapSupplement<Navigator>::from(navigator, supplementName()));
 }
 
 const char* NavigatorServiceWorker::supplementName()
@@ skipping 17 matching lines @@
 
 void NavigatorServiceWorker::willDetachGlobalObjectFromFrame()
 {
     if (m_serviceWorker) {
         m_serviceWorker->detachClient();
         m_serviceWorker = nullptr;
     }
 }
 
 } // namespace WebCore