Bug 1343550 - Prevent creating AudioNodes on an AudioContext that has been disconnected from its owner. r=baku

Spec (being written): https://github.com/WebAudio/web-audio-api/issues/1139

Bug 1343550 - Prevent touching promises when shutting down an AudioContext, when the global is going away soon. r=baku

MozReview-Commit-ID: F6en9KEbNNf

--HG--
extra : rebase_source : 04076caa38bba980cdff776b5997f33e24516d9e
extra : intermediate-source : 4f2cd3f715a218dc3bca55e89720b6aa1040d35c
extra : source : 69cd9c72bd4ed419e3f7f7b5ab64ee0fa8bd89a2

dom/media/webaudio/AudioContext.cpp

@@ -140,6 +140,7 @@ AudioContext::AudioContext(nsPIDOMWindowInner* aWindow,
   , mIsShutDown(false)
   , mCloseCalled(false)
   , mSuspendCalled(false)
+  , mIsDisconnecting(false)
 {
   bool mute = aWindow->AddAudioContext(this);
 
@@ -260,7 +261,9 @@ AudioContext::Constructor(const GlobalObject& aGlobal,
 
 bool AudioContext::CheckClosed(ErrorResult& aRv)
 {
-  if (mAudioContextState == AudioContextState::Closed) {
+  if (mAudioContextState == AudioContextState::Closed ||
+      mIsShutDown ||
+      mIsDisconnecting) {
     aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
     return true;
   }
@@ -640,21 +643,31 @@ AudioContext::CurrentTime() const
   return stream->StreamTimeToSeconds(stream->GetCurrentTime());
 }
 
+void AudioContext::DisconnectFromOwner()
+{
+  mIsDisconnecting = true;
+  Shutdown();
+  DOMEventTargetHelper::DisconnectFromOwner();
+}
+
 void
 AudioContext::Shutdown()
 {
   mIsShutDown = true;
 
-  if (!mIsOffline) {
-    ErrorResult dummy;
-    RefPtr<Promise> ignored = Close(dummy);
-  }
+  // We don't want to touch promises if the global is going away soon.
+  if (!mIsDisconnecting) {
+    if (!mIsOffline) {
+      IgnoredErrorResult dummy;
+      RefPtr<Promise> ignored = Close(dummy);
+    }
 
-  for (auto p : mPromiseGripArray) {
-    p->MaybeReject(NS_ERROR_DOM_INVALID_STATE_ERR);
-  }
+    for (auto p : mPromiseGripArray) {
+      p->MaybeReject(NS_ERROR_DOM_INVALID_STATE_ERR);
+    }
 
-  mPromiseGripArray.Clear();
+    mPromiseGripArray.Clear();
+  }
 
   // Release references to active nodes.
   // Active AudioNodes don't unregister in destructors, at which point the

dom/media/webaudio/AudioContext.h

@@ -142,6 +142,8 @@ public:
     return GetOwner();
   }
 
+  virtual void DisconnectFromOwner() override;
+
   void Shutdown(); // idempotent
 
   JSObject* WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override;
@@ -372,6 +374,7 @@ private:
   bool mCloseCalled;
   // Suspend has been called with no following resume.
   bool mSuspendCalled;
+  bool mIsDisconnecting;
 };
 
 static const dom::AudioContext::AudioContextId NO_AUDIO_CONTEXT = 0;