From d358897d780bd0bda9b52c22d2e4c59c4276bd4b Mon Sep 17 00:00:00 2001
From: Andrea Marchesini <amarchesini@mozilla.com>
Date: Thu, 15 Jan 2015 16:58:41 +0000
Subject: [PATCH] Bug 966439 - BroadcastChannel API - patch 5 - bfcache
 supported, r=smaug

---
 dom/broadcastchannel/BroadcastChannel.cpp     | 27 +++++++++++++++++--
 .../BroadcastChannelChild.cpp                 | 24 ++++++++++-------
 dom/broadcastchannel/BroadcastChannelChild.h  |  9 +++----
 3 files changed, 43 insertions(+), 17 deletions(-)

diff --git a/dom/broadcastchannel/BroadcastChannel.cpp b/dom/broadcastchannel/BroadcastChannel.cpp
index 1782cdc35ad..3848ba606a7 100644
--- a/dom/broadcastchannel/BroadcastChannel.cpp
+++ b/dom/broadcastchannel/BroadcastChannel.cpp
@@ -125,6 +125,24 @@ public:
       return true;
     }
 
+    // Walk up to our containing page
+    WorkerPrivate* wp = mWorkerPrivate;
+    while (wp->GetParent()) {
+      wp = wp->GetParent();
+    }
+
+    // Window doesn't exist for some kind of workers (eg: SharedWorkers)
+    nsPIDOMWindow* window = wp->GetWindow();
+    if (!window) {
+      return true;
+    }
+
+    nsIDocument* doc = window->GetExtantDoc();
+    // No bfcache when BroadcastChannel is used.
+    if (doc) {
+      doc->DisallowBFCaching();
+    }
+
     return true;
   }
 
@@ -400,6 +418,11 @@ BroadcastChannel::Constructor(const GlobalObject& aGlobal,
       return nullptr;
     }
 
+    nsIDocument* doc = window->GetExtantDoc();
+    // No bfcache when BroadcastChannel is used.
+    if (doc) {
+      doc->DisallowBFCaching();
+    }
   } else {
     JSContext* cx = aGlobal.Context();
     workerPrivate = GetWorkerPrivateFromContext(cx);
@@ -506,7 +529,7 @@ BroadcastChannel::ActorCreated(ipc::PBackgroundChild* aActor)
   mActor = static_cast<BroadcastChannelChild*>(actor);
   MOZ_ASSERT(mActor);
 
-  mActor->SetEventTarget(this);
+  mActor->SetParent(this);
 
   // Flush pending messages.
   for (uint32_t i = 0; i < mPendingMessages.Length(); ++i) {
@@ -539,7 +562,7 @@ BroadcastChannel::Shutdown()
   }
 
   if (mActor) {
-    mActor->SetEventTarget(nullptr);
+    mActor->SetParent(nullptr);
 
     nsRefPtr<TeardownRunnable> runnable = new TeardownRunnable(mActor);
     NS_DispatchToCurrentThread(runnable);
diff --git a/dom/broadcastchannel/BroadcastChannelChild.cpp b/dom/broadcastchannel/BroadcastChannelChild.cpp
index 272d33b96ff..b420a3c6c17 100644
--- a/dom/broadcastchannel/BroadcastChannelChild.cpp
+++ b/dom/broadcastchannel/BroadcastChannelChild.cpp
@@ -30,24 +30,29 @@ BroadcastChannelChild::BroadcastChannelChild(const nsAString& aOrigin,
 
 BroadcastChannelChild::~BroadcastChannelChild()
 {
-  MOZ_ASSERT(!mEventTarget);
+  MOZ_ASSERT(!mBC);
 }
 
 bool
 BroadcastChannelChild::RecvNotify(const nsString& aMessage)
 {
+  nsCOMPtr<DOMEventTargetHelper> helper = mBC;
+  nsCOMPtr<EventTarget> eventTarget = do_QueryInterface(helper);
+
   // This object is going to be deleted soon. No notify is required.
-  if (!mEventTarget) {
+  if (!eventTarget) {
+    return true;
+  }
+
+  // CheckInnerWindowCorrectness can be used also without a window when
+  // BroadcastChannel is running in a worker. In this case, it's a NOP.
+  if (NS_FAILED(mBC->CheckInnerWindowCorrectness())) {
     return true;
   }
 
   if (NS_IsMainThread()) {
-    DOMEventTargetHelper* deth =
-      DOMEventTargetHelper::FromSupports(mEventTarget);
-    MOZ_ASSERT(deth);
-
     AutoJSAPI autoJS;
-    if (!autoJS.Init(deth->GetParentObject())) {
+    if (!autoJS.Init(mBC->GetParentObject())) {
       NS_WARNING("Dropping message");
       return true;
     }
@@ -85,8 +90,7 @@ BroadcastChannelChild::Notify(JSContext* aCx, const nsString& aMessage)
 
   ErrorResult rv;
   nsRefPtr<MessageEvent> event =
-    MessageEvent::Constructor(mEventTarget, NS_LITERAL_STRING("message"),
-                              init, rv);
+    MessageEvent::Constructor(mBC, NS_LITERAL_STRING("message"), init, rv);
   if (rv.Failed()) {
     NS_WARNING("Failed to create a MessageEvent object.");
     return;
@@ -95,7 +99,7 @@ BroadcastChannelChild::Notify(JSContext* aCx, const nsString& aMessage)
   event->SetTrusted(true);
 
   bool status;
-  mEventTarget->DispatchEvent(static_cast<Event*>(event.get()), &status);
+  mBC->DispatchEvent(static_cast<Event*>(event.get()), &status);
 }
 
 void
diff --git a/dom/broadcastchannel/BroadcastChannelChild.h b/dom/broadcastchannel/BroadcastChannelChild.h
index d04e74b651d..7a3329e763d 100644
--- a/dom/broadcastchannel/BroadcastChannelChild.h
+++ b/dom/broadcastchannel/BroadcastChannelChild.h
@@ -5,7 +5,6 @@
 #ifndef mozilla_dom_BroadcastChannelChild_h
 #define mozilla_dom_BroadcastChannelChild_h
 
-#include "mozilla/dom/EventTarget.h"
 #include "mozilla/dom/PBroadcastChannelChild.h"
 
 namespace mozilla {
@@ -16,7 +15,7 @@ class BackgroundChildImpl;
 
 namespace dom {
 
-class EventTarget;
+class BroadcastChannel;
 
 class BroadcastChannelChild MOZ_FINAL : public PBroadcastChannelChild
 {
@@ -25,9 +24,9 @@ class BroadcastChannelChild MOZ_FINAL : public PBroadcastChannelChild
 public:
   NS_INLINE_DECL_REFCOUNTING(BroadcastChannelChild)
 
-  void SetEventTarget(EventTarget* aEventTarget)
+  void SetParent(BroadcastChannel* aBC)
   {
-    mEventTarget = aEventTarget;
+    mBC = aBC;
   }
 
   virtual bool RecvNotify(const nsString& aMessage) MOZ_OVERRIDE;
@@ -49,7 +48,7 @@ private:
 
   // This raw pointer is actually the parent object.
   // It's set to null when the parent object is deleted.
-  EventTarget* mEventTarget;
+  BroadcastChannel* mBC;
 
   nsString mOrigin;
   nsString mChannel;