Media: harden TrackID handling.

1 files changed, 5 insertions, 1 deletions

diff --git a/dom/media/MediaDecoder.h b/dom/media/MediaDecoder.h
index 825bbbd2c..a4edcbe72 100644
--- a/dom/media/MediaDecoder.h
+++ b/dom/media/MediaDecoder.h
@@ -210,9 +210,13 @@ public:
   // Add an output stream. All decoder output will be sent to the stream.
   // The stream is initially blocked. The decoder is responsible for unblocking
   // it while it is playing back.
-  virtual void AddOutputStream(ProcessedMediaStream* aStream, bool aFinishWhenEnded);
+  virtual void AddOutputStream(ProcessedMediaStream* aStream,
+                               TrackID aNextAvailableTrackID,
+                               bool aFinishWhenEnded);
   // Remove an output stream added with AddOutputStream.
   virtual void RemoveOutputStream(MediaStream* aStream);
+  // The next TrackID that can be used without risk of a collision.
+  virtual TrackID NextAvailableTrackIDFor(MediaStream* aOutputStream) const;
 
   // Return the duration of the video in seconds.
   virtual double GetDuration();