Bug 1172264 - Route mExplicitDuration directly from the mediasource code to MediaDecoder, and stop passing an argument to DurationChanged. r=pending=jww

dom/media/MediaDecoder.cpp

@@ -304,10 +304,6 @@ void MediaDecoder::AddOutputStream(ProcessedMediaStream* aStream,
 double MediaDecoder::GetDuration()
 {
   MOZ_ASSERT(NS_IsMainThread());
-  if (mInfiniteStream) {
-    return std::numeric_limits<double>::infinity();
-  }
-
   return mDuration;
 }
 
@@ -322,6 +318,7 @@ void MediaDecoder::SetInfinite(bool aInfinite)
 {
   MOZ_ASSERT(NS_IsMainThread());
   mInfiniteStream = aInfinite;
+  DurationChanged();
 }
 
 bool MediaDecoder::IsInfinite()
@@ -366,6 +363,7 @@ MediaDecoder::MediaDecoder() :
   mPausedForPlaybackRateNull(false),
   mMinimizePreroll(false),
   mMediaTracksConstructed(false),
+  mFiredMetadataLoaded(false),
   mIsDormant(false),
   mWasEndedWhenEnteredDormant(false),
   mIsHeuristicDormantSupported(
@@ -669,6 +667,7 @@ void MediaDecoder::MetadataLoaded(nsAutoPtr<MediaInfo> aInfo,
     // our new size.
     Invalidate();
     if (aEventVisibility != MediaDecoderEventVisibility::Suppressed) {
+      mFiredMetadataLoaded = true;
       mOwner->MetadataLoaded(mInfo, nsAutoPtr<const MetadataTags>(aTags.forget()));
     }
   }
@@ -1078,22 +1077,38 @@ void MediaDecoder::UpdateLogicalPosition(MediaDecoderEventVisibility aEventVisib
   }
 }
 
-void MediaDecoder::DurationChanged(TimeUnit aNewDuration)
+void MediaDecoder::DurationChanged()
 {
   MOZ_ASSERT(NS_IsMainThread());
   ReentrantMonitorAutoEnter mon(GetReentrantMonitor());
+
   double oldDuration = mDuration;
-  mDuration = aNewDuration.ToSeconds();
+  if (IsInfinite()) {
+    mDuration = std::numeric_limits<double>::infinity();
+  } else if (mExplicitDuration.Ref().isSome()) {
+    mDuration = mExplicitDuration.Ref().ref();
+  } else if (mStateMachineDuration.Ref().isSome()) {
+    mDuration = mStateMachineDuration.Ref().ref().ToSeconds();
+  }
+
+  if (mDuration == oldDuration || IsNaN(mDuration)) {
+    return;
+  }
+
+  DECODER_LOG("Duration changed to %f", mDuration);
+
   // Duration has changed so we should recompute playback rate
   UpdatePlaybackRate();
 
-  if (mOwner && oldDuration != mDuration && !IsInfinite()) {
-    DECODER_LOG("Duration changed to %f", mDuration);
+  // See https://www.w3.org/Bugs/Public/show_bug.cgi?id=28822 for a discussion
+  // of whether we should fire durationchange on explicit infinity.
+  if (mOwner && mFiredMetadataLoaded &&
+      (!mozilla::IsInfinite<double>(mDuration) || mExplicitDuration.Ref().isSome())) {
     mOwner->DispatchAsyncEvent(NS_LITERAL_STRING("durationchange"));
   }
 
-  if (CurrentPosition() > aNewDuration.ToMicroseconds()) {
-    Seek(aNewDuration.ToSeconds(), SeekTarget::Accurate);
+  if (CurrentPosition() > TimeUnit::FromSeconds(mDuration).ToMicroseconds()) {
+    Seek(mDuration, SeekTarget::Accurate);
   }
 }
 

dom/media/MediaDecoder.h

@@ -512,7 +512,7 @@ public:
 
   // Called by the state machine to notify the decoder that the duration
   // has changed.
-  void DurationChanged(media::TimeUnit aNewDuration);
+  void DurationChanged();
 
   bool OnStateMachineTaskQueue() const override;
 
@@ -996,7 +996,15 @@ protected:
   // for MSE.
   Canonical<Maybe<double>> mExplicitDuration;
   double ExplicitDuration() { return mExplicitDuration.Ref().ref(); }
-  void SetExplicitDuration(double aValue) { mExplicitDuration.Set(Some(aValue)); }
+  void SetExplicitDuration(double aValue)
+  {
+    mExplicitDuration.Set(Some(aValue));
+
+    // We Invoke DurationChanged explicitly, rather than using a watcher, so
+    // that it takes effect immediately, rather than at the end of the current task.
+    DurationChanged();
+  }
+
 public:
   AbstractCanonical<Maybe<double>>* CanonicalExplicitDuration() { return &mExplicitDuration; }
 protected:
@@ -1088,6 +1096,9 @@ protected:
   // track list, false if all tracks are removed from the track list.
   bool mMediaTracksConstructed;
 
+  // True if we've already fired metadataloaded.
+  bool mFiredMetadataLoaded;
+
   // Stores media info, including info of audio tracks and video tracks, should
   // only be accessed from main thread.
   nsAutoPtr<MediaInfo> mInfo;

dom/media/MediaDecoderStateMachine.cpp

@@ -1420,8 +1420,7 @@ void MediaDecoderStateMachine::RecomputeDuration()
   mDuration = Some(duration);
 
   if (fireDurationChanged) {
-    nsCOMPtr<nsIRunnable> event =
-      NS_NewRunnableMethodWithArg<TimeUnit>(mDecoder, &MediaDecoder::DurationChanged, duration);
+    nsCOMPtr<nsIRunnable> event = NS_NewRunnableMethod(mDecoder, &MediaDecoder::DurationChanged);
     AbstractThread::MainThread()->Dispatch(event.forget());
   }
 }

dom/media/mediasource/MediaSourceDecoder.cpp

@@ -221,7 +221,6 @@ MediaSourceDecoder::SetMediaSourceDuration(double aDuration, MSRangeRemovalActio
     GetReader()->SetMediaSourceDuration(ExplicitDuration());
   }
 
-  MediaDecoder::DurationChanged(TimeUnit::FromSeconds(ExplicitDuration()));
   if (mMediaSource && aAction != MSRangeRemovalAction::SKIP) {
     mMediaSource->DurationChange(oldDuration, aDuration);
   }