Bug 1163227: Part2. Add MediaDecoderReader::NotifyDataRemoved method. r=cpearce

dom/media/MediaDataDemuxer.h

@@ -85,6 +85,12 @@ public:
   // data is available.
   virtual void NotifyDataArrived(uint32_t aLength, int64_t aOffset) { }
 
+  // Notifies the demuxer that the underlying resource has had data removed.
+  // The demuxer can use this mechanism to inform all track demuxers to update
+  // its TimeIntervals.
+  // This will be called should the demuxer be used with MediaSource.
+  virtual void NotifyDataRemoved() { }
+
 protected:
   virtual ~MediaDataDemuxer()
   {

dom/media/MediaDecoderReader.h

@@ -247,6 +247,8 @@ public:
   // Only used by WebMReader and MediaOmxReader for now, so stub here rather
   // than in every reader than inherits from MediaDecoderReader.
   virtual void NotifyDataArrived(const char* aBuffer, uint32_t aLength, int64_t aOffset) {}
+  // Notify the reader that data from the resource was evicted (MediaSource only)
+  virtual void NotifyDataRemoved() {}
   virtual int64_t GetEvictionOffset(double aTime) { return -1; }
 
   virtual MediaQueue<AudioData>& AudioQueue() { return mAudioQueue; }

dom/media/MediaFormatReader.cpp

@@ -1334,7 +1334,11 @@ MediaFormatReader::NotifyDemuxer(uint32_t aLength, int64_t aOffset)
     return;
   }
 
-  mDemuxer->NotifyDataArrived(aLength, aOffset);
+  if (aLength || aOffset) {
+    mDemuxer->NotifyDataArrived(aLength, aOffset);
+  } else {
+    mDemuxer->NotifyDataRemoved();
+  }
   if (HasVideo()) {
     mVideo.mReceivedNewData = true;
     ScheduleUpdate(TrackType::kVideoTrack);
@@ -1355,6 +1359,7 @@ MediaFormatReader::NotifyDataArrived(const char* aBuffer, uint32_t aLength, int6
   }
 
   MOZ_ASSERT(mMainThreadDemuxer);
+  MOZ_ASSERT(aBuffer || aLength);
   mMainThreadDemuxer->NotifyDataArrived(aLength, aOffset);
 
   // Queue a task to notify our main demuxer.
@@ -1365,4 +1370,24 @@ MediaFormatReader::NotifyDataArrived(const char* aBuffer, uint32_t aLength, int6
   GetTaskQueue()->Dispatch(task.forget());
 }
 
+void
+MediaFormatReader::NotifyDataRemoved()
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!mInitDone) {
+    return;
+  }
+
+  MOZ_ASSERT(mMainThreadDemuxer);
+  mMainThreadDemuxer->NotifyDataRemoved();
+
+  // Queue a task to notify our main demuxer.
+  RefPtr<nsIRunnable> task =
+    NS_NewRunnableMethodWithArgs<int32_t, uint64_t>(
+      this, &MediaFormatReader::NotifyDemuxer,
+      0, 0);
+  GetTaskQueue()->Dispatch(task.forget());
+}
+
 } // namespace mozilla

dom/media/MediaFormatReader.h

@@ -76,6 +76,7 @@ public:
   virtual void NotifyDataArrived(const char* aBuffer,
                                  uint32_t aLength,
                                  int64_t aOffset) override;
+  virtual void NotifyDataRemoved() override;
 
   virtual media::TimeIntervals GetBuffered() override;
 

dom/media/fmp4/MP4Demuxer.cpp

@@ -114,6 +114,14 @@ MP4Demuxer::NotifyDataArrived(uint32_t aLength, int64_t aOffset)
   }
 }
 
+void
+MP4Demuxer::NotifyDataRemoved()
+{
+  for (uint32_t i = 0; i < mDemuxers.Length(); i++) {
+    mDemuxers[i]->NotifyDataArrived();
+  }
+}
+
 UniquePtr<EncryptionInfo>
 MP4Demuxer::GetCrypto()
 {

dom/media/fmp4/MP4Demuxer.h

@@ -45,6 +45,8 @@ public:
 
   virtual void NotifyDataArrived(uint32_t aLength, int64_t aOffset) override;
 
+  virtual void NotifyDataRemoved() override;
+
 private:
   friend class MP4TrackDemuxer;
   nsRefPtr<MediaResource> mResource;