Remove Page dependency from NetworkStateNotifier

third_party/WebKit/Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All
  * rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
@@ skipping 187 matching lines @@
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/loader/ImageLoader.h"
 #include "core/loader/NavigationScheduler.h"
 #include "core/loader/PrerendererClient.h"
 #include "core/loader/appcache/ApplicationCacheHost.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/EventWithHitTestResults.h"
 #include "core/page/FocusController.h"
 #include "core/page/FrameTree.h"
+#include "core/page/NetworkStateNotifier.h"
 #include "core/page/Page.h"
 #include "core/page/PointerLockController.h"
 #include "core/page/scrolling/RootScrollerController.h"
 #include "core/page/scrolling/ScrollStateCallback.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
 #include "core/page/scrolling/SnapCoordinator.h"
 #include "core/page/scrolling/TopDocumentRootScrollerController.h"
 #include "core/svg/SVGDocumentExtensions.h"
 #include "core/svg/SVGScriptElement.h"
 #include "core/svg/SVGTitleElement.h"
@@ skipping 179 matching lines @@
   }
 }
 
 static void recordLoadReasonToHistogram(WouldLoadReason reason) {
   DEFINE_STATIC_LOCAL(
       EnumerationHistogram, unseenFrameHistogram,
       ("Navigation.DeferredDocumentLoading.StatesV3", WouldLoadReasonEnd));
   unseenFrameHistogram.count(reason);
 }
 
+class Document::NetworkStateObserver final
+    : public GarbageCollected<Document::NetworkStateObserver>,
+      public NetworkStateNotifier::NetworkStateObserver,
+      public ContextLifecycleObserver {
+  USING_GARBAGE_COLLECTED_MIXIN(Document::NetworkStateObserver);
+
+ public:
+  NetworkStateObserver(Document& document)

[dcheng, 2017/02/22 09:23:15]

Nit: explicit

[kinuko, 2017/02/22 13:17:27]

Done.

+      : ContextLifecycleObserver(document), m_document(&document) {
+    networkStateNotifier().addOnLineObserver(
+        this, TaskRunnerHelper::get(TaskType::Networking, m_document).get());

[dcheng, 2017/02/22 09:23:15]

Is it safe to pass (and store) the WebTaskRunner as a raw pointer?

[kinuko, 2017/02/22 13:17:27]

Hmm, there was an assumption that the task runner must be alive while the
associated execution context's alive, but it might not be really guaranteed. 
Fixed.

+  }
+
+  void onLineStateChange(bool onLine) override {
+    AtomicString eventName =
+        onLine ? EventTypeNames::online : EventTypeNames::offline;
+    m_document->domWindow()->dispatchEvent(Event::create(eventName));
+    InspectorInstrumentation::networkStateChanged(m_document->frame(), onLine);
+  }
+
+  void contextDestroyed(ExecutionContext* context) override {
+    networkStateNotifier().removeOnLineObserver(
+        this, TaskRunnerHelper::get(TaskType::Networking, context).get());
+  }
+
+  DEFINE_INLINE_VIRTUAL_TRACE() {
+    visitor->trace(m_document);
+    ContextLifecycleObserver::trace(visitor);
+  }
+
+ private:
+  Member<Document> m_document;
+};
+
 Document::Document(const DocumentInit& initializer,
                    DocumentClassFlags documentClasses)
     : ContainerNode(0, CreateDocument),
       TreeScope(*this),
       m_hasNodesWithPlaceholderStyle(false),
       m_evaluateMediaQueriesOnStyleRecalc(false),
       m_pendingSheetLayout(NoLayoutWithPendingSheets),
       m_frame(initializer.frame()),
       // TODO(dcheng): Why does this need both a LocalFrame and LocalDOMWindow
       // pointer?
@@ skipping 72 matching lines @@
       m_didAssociateFormControlsTimer(
           TaskRunnerHelper::get(TaskType::UnspecedLoading, this),
           this,
           &Document::didAssociateFormControlsTimerFired),
       m_timers(TaskRunnerHelper::get(TaskType::Timer, this)),
       m_hasViewportUnits(false),
       m_parserSyncPolicy(AllowAsynchronousParsing),
       m_nodeCount(0),
       m_wouldLoadReason(Created),
       m_passwordCount(0),
-      m_engagementLevel(mojom::blink::EngagementLevel::NONE) {
+      m_engagementLevel(mojom::blink::EngagementLevel::NONE),
+      m_networkStateObserver(new NetworkStateObserver(*this)) {
   if (m_frame) {
     DCHECK(m_frame->page());
     provideContextFeaturesToDocumentFrom(*this, *m_frame->page());
 
     m_fetcher = m_frame->loader().documentLoader()->fetcher();
     FrameFetchContext::provideDocumentToContext(m_fetcher->context(), this);
 
     // TODO(dcheng): Why does this need to check that DOMWindow is non-null?
     CustomElementRegistry* registry =
         m_frame->domWindow() ? m_frame->domWindow()->maybeCustomElements()
@@ skipping 6033 matching lines @@
   visitor->trace(m_svgExtensions);
   visitor->trace(m_timeline);
   visitor->trace(m_compositorPendingAnimations);
   visitor->trace(m_contextDocument);
   visitor->trace(m_canvasFontCache);
   visitor->trace(m_intersectionObserverController);
   visitor->trace(m_snapCoordinator);
   visitor->trace(m_resizeObserverController);
   visitor->trace(m_propertyRegistry);
   visitor->trace(m_styleReattachDataMap);
+  visitor->trace(m_networkStateObserver);
   Supplementable<Document>::trace(visitor);
   TreeScope::trace(visitor);
   ContainerNode::trace(visitor);
   ExecutionContext::trace(visitor);
   SecurityContext::trace(visitor);
   SynchronousMutationNotifier::trace(visitor);
 }
 
 void Document::maybeRecordLoadReason(WouldLoadReason reason) {
   DCHECK(m_wouldLoadReason == Created || reason != Created);
@@ skipping 40 matching lines @@
 }
 
 void showLiveDocumentInstances() {
   WeakDocumentSet& set = liveDocumentSet();
   fprintf(stderr, "There are %u documents currently alive:\n", set.size());
   for (blink::Document* document : set)
     fprintf(stderr, "- Document %p URL: %s\n", document,
             document->url().getString().utf8().data());
 }
 #endif