Bug 1208378 - Implement MediaStreamTrack's muted state and events. r=jib,smaug

MozReview-Commit-ID: 1Sp9utMnWXI

--HG--
extra : rebase_source : f2d1036ab37ed9882c0bb9aa1d7b7d68eb7799e4

dom/base/nsGkAtomList.h

@@ -726,6 +726,7 @@ GK_ATOM(moz_action_hint, "mozactionhint")
 GK_ATOM(x_moz_errormessage, "x-moz-errormessage")
 GK_ATOM(multicol, "multicol")
 GK_ATOM(multiple, "multiple")
+GK_ATOM(mute, "mute")
 GK_ATOM(muted, "muted")
 GK_ATOM(name, "name")
 GK_ATOM(_namespace, "namespace")
@@ -946,6 +947,7 @@ GK_ATOM(onmapgetmessagereq, "onmapgetmessagereq")
 GK_ATOM(onmapsetmessagestatusreq, "onmapsetmessagestatusreq")
 GK_ATOM(onmapsendmessagereq, "onmapsendmessagereq")
 GK_ATOM(onmapmessageupdatereq, "onmapmessageupdatereq")
+GK_ATOM(onmute, "onmute")
 GK_ATOM(onnewrdsgroup, "onnewrdsgroup")
 GK_ATOM(onnotificationclick, "onnotificationclick")
 GK_ATOM(onnotificationclose, "onnotificationclose")
@@ -1037,6 +1039,7 @@ GK_ATOM(ontransitionrun, "ontransitionrun")
 GK_ATOM(ontransitionstart, "ontransitionstart")
 GK_ATOM(onunderflow, "onunderflow")
 GK_ATOM(onunload, "onunload")
+GK_ATOM(onunmute, "onunmute")
 GK_ATOM(onupdatefound, "onupdatefound")
 GK_ATOM(onupdateready, "onupdateready")
 GK_ATOM(onupgradeneeded, "onupgradeneeded")
@@ -1388,6 +1391,7 @@ GK_ATOM(ul, "ul")
 GK_ATOM(underflow, "underflow")
 GK_ATOM(undetermined, "undetermined")
 GK_ATOM(unload, "unload")
+GK_ATOM(unmute, "unmute")
 GK_ATOM(unparsedEntityUri, "unparsed-entity-uri")
 GK_ATOM(upperAlpha, "upper-alpha")
 GK_ATOM(upperFirst, "upper-first")

dom/html/HTMLMediaElement.cpp

@@ -3209,6 +3209,16 @@ public:
     MediaStreamTrackSource::PrincipalChanged();
   }
 
+  void MutedChanged(bool aNewState) override
+  {
+    if (!mCapturedTrackSource) {
+      // This could happen during shutdown.
+      return;
+    }
+
+    MediaStreamTrackSource::MutedChanged(aNewState);
+  }
+
 private:
   virtual ~StreamCaptureTrackSource() {}
 

dom/media/DOMMediaStream.cpp

@@ -1204,6 +1204,7 @@ DOMMediaStream::CloneDOMTrack(MediaStreamTrack& aTrack,
   NotifyTrackAdded(newTrack);
 
   newTrack->SetEnabled(aTrack.Enabled());
+  newTrack->SetMuted(aTrack.Muted());
   newTrack->SetReadyState(aTrack.ReadyState());
 
   if (aTrack.Ended()) {

dom/media/MediaStreamTrack.cpp

@@ -124,7 +124,7 @@ MediaStreamTrack::MediaStreamTrack(DOMMediaStream* aStream, TrackID aTrackID,
     mInputTrackID(aInputTrackID), mSource(aSource),
     mPrincipal(aSource->GetPrincipal()),
     mReadyState(MediaStreamTrackState::Live),
-    mEnabled(true), mConstraints(aConstraints)
+    mEnabled(true), mMuted(false), mConstraints(aConstraints)
 {
   GetSource().RegisterSink(this);
 
@@ -373,6 +373,25 @@ MediaStreamTrack::NotifyPrincipalHandleChanged(const PrincipalHandle& aNewPrinci
   }
 }
 
+void
+MediaStreamTrack::MutedChanged(bool aNewState)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (mMuted == aNewState) {
+    MOZ_ASSERT_UNREACHABLE("Muted state didn't actually change");
+    return;
+  }
+
+  LOG(LogLevel::Info, ("MediaStreamTrack %p became %s",
+                       this, aNewState ? "muted" : "unmuted"));
+
+  mMuted = aNewState;
+  nsString eventName =
+    aNewState ? NS_LITERAL_STRING("mute") : NS_LITERAL_STRING("unmute");
+  DispatchTrustedEvent(eventName);
+}
+
 void
 MediaStreamTrack::NotifyEnded()
 {

dom/media/MediaStreamTrack.h

@@ -62,6 +62,7 @@ public:
   public:
     MOZ_DECLARE_WEAKREFERENCE_TYPENAME(MediaStreamTrackSource::Sink)
     virtual void PrincipalChanged() = 0;
+    virtual void MutedChanged(bool aNewState) = 0;
   };
 
   MediaStreamTrackSource(nsIPrincipal* aPrincipal,
@@ -196,6 +197,25 @@ protected:
     }
   }
 
+  /**
+   * Called by a sub class when the source's muted state has changed. Note that
+   * the source is responsible for making the content black/silent during mute.
+   * Notifies all sinks.
+   */
+  void MutedChanged(bool aNewState)
+  {
+    MOZ_ASSERT(NS_IsMainThread());
+    nsTArray<WeakPtr<Sink>> sinks(mSinks);
+    for (auto& sink : sinks) {
+      if (!sink) {
+        MOZ_ASSERT_UNREACHABLE("Sink was not explicitly removed");
+        mSinks.RemoveElement(sink);
+        continue;
+      }
+      sink->MutedChanged(aNewState);
+    }
+  }
+
   // Principal identifying who may access the contents of this source.
   nsCOMPtr<nsIPrincipal> mPrincipal;
 
@@ -298,6 +318,7 @@ public:
   virtual void GetLabel(nsAString& aLabel, CallerType /* aCallerType */) { GetSource().GetLabel(aLabel); }
   bool Enabled() { return mEnabled; }
   void SetEnabled(bool aEnabled);
+  bool Muted() { return mMuted; }
   void Stop();
   void GetConstraints(dom::MediaTrackConstraints& aResult);
   void GetSettings(dom::MediaTrackSettings& aResult, CallerType aCallerType);
@@ -308,6 +329,8 @@ public:
   already_AddRefed<MediaStreamTrack> Clone();
   MediaStreamTrackState ReadyState() { return mReadyState; }
 
+  IMPL_EVENT_HANDLER(mute)
+  IMPL_EVENT_HANDLER(unmute)
   IMPL_EVENT_HANDLER(ended)
 
   /**
@@ -373,6 +396,16 @@ public:
 
   // Implementation of MediaStreamTrackSource::Sink
   void PrincipalChanged() override;
+  /**
+   * 4.3.1 Life-cycle and Media flow - Media flow
+   * To set a track's muted state to newState, the User Agent MUST run the
+   * following steps:
+   *  1. Let track be the MediaStreamTrack in question.
+   *  2. Set track's muted attribute to newState.
+   *  3. If newState is true let eventName be mute, otherwise unmute.
+   *  4. Fire a simple event named eventName on track.
+   */
+  void MutedChanged(bool aNewState) override;
 
   /**
    * Add a PrincipalChangeObserver to this track.
@@ -442,6 +475,11 @@ public:
 protected:
   virtual ~MediaStreamTrack();
 
+  /**
+   * Sets this track's muted state without raising any events.
+   */
+  void SetMuted(bool aMuted) { mMuted = aMuted; }
+
   void Destroy();
 
   // Returns the original DOMMediaStream's underlying input stream.
@@ -486,6 +524,7 @@ protected:
   nsString mID;
   MediaStreamTrackState mReadyState;
   bool mEnabled;
+  bool mMuted;
   dom::MediaTrackConstraints mConstraints;
 };
 

dom/webidl/MediaStreamTrack.webidl

@@ -80,11 +80,9 @@ interface MediaStreamTrack : EventTarget {
     [NeedsCallerType]
     readonly    attribute DOMString             label;
                 attribute boolean               enabled;
-//  readonly    attribute boolean               muted;
-//              attribute EventHandler          onmute;
-//              attribute EventHandler          onunmute;
-//  readonly    attribute boolean               _readonly;
-//  readonly    attribute boolean               remote;
+    readonly    attribute boolean               muted;
+                attribute EventHandler          onmute;
+                attribute EventHandler          onunmute;
     readonly    attribute MediaStreamTrackState readyState;
                 attribute EventHandler          onended;
     MediaStreamTrack       clone ();