--- a/dom/media/MediaDecoderStateMachine.cpp
+++ b/dom/media/MediaDecoderStateMachine.cpp
@@ -3759,23 +3759,16 @@ MediaDecoderStateMachine::SetPlaybackRat
 }
 
 void MediaDecoderStateMachine::PreservesPitchChanged()
 {
   MOZ_ASSERT(OnTaskQueue());
   mMediaSink->SetPreservesPitch(mPreservesPitch);
 }
 
-bool
-MediaDecoderStateMachine::IsShutdown() const
-{
-  MOZ_ASSERT(OnTaskQueue());
-  return mIsShutdown;
-}
-
 TimeUnit
 MediaDecoderStateMachine::AudioEndTime() const
 {
   MOZ_ASSERT(OnTaskQueue());
   if (mMediaSink->IsStarted()) {
     return mMediaSink->GetEndTime(TrackInfo::kAudioTrack);
   }
   return TimeUnit::Zero();

--- a/dom/media/MediaDecoderStateMachine.h
+++ b/dom/media/MediaDecoderStateMachine.h
@@ -300,19 +300,16 @@ private:
   // Invokes ScheduleStateMachine to run in |aTime|,
   // unless it's already scheduled to run earlier, in which case the
   // request is discarded.
   void ScheduleStateMachineIn(const media::TimeUnit& aTime);
 
   bool HaveEnoughDecodedAudio();
   bool HaveEnoughDecodedVideo();
 
-  // True if shutdown process has begun.
-  bool IsShutdown() const;
-
   // Returns true if we're currently playing. The decoder monitor must
   // be held.
   bool IsPlaying() const;
 
   // Sets mMediaSeekable to false.
   void SetMediaNotSeekable();
 
   // Resets all states related to decoding and aborts all pending requests