Fix 99596.

media/filters/ffmpeg_demuxer.cc

Index: media/filters/ffmpeg_demuxer.cc
diff --git a/media/filters/ffmpeg_demuxer.cc b/media/filters/ffmpeg_demuxer.cc
index f59c665a0ed35d73fea6e9fa8c34e02b86108bd6..2860c0cc05a1dcc5b1af4408d0485fea40ec74d4 100644
--- a/media/filters/ffmpeg_demuxer.cc
+++ b/media/filters/ffmpeg_demuxer.cc
@@ -160,6 +160,15 @@ void FFmpegDemuxerStream::Read(const ReadCallback& read_callback) {
   DCHECK(!read_callback.is_null());
 
   base::AutoLock auto_lock(lock_);
+  // Don't accept any additional reads if we've been told to stop.
+  // The demuxer_ may have been destroyed in the pipleine thread.
+  //
+  // TODO(scherkus): it would be cleaner if we replied with an error message.
+  if (stopped_) {
+    read_callback.Run(new DataBuffer(0));
+    return;
+  }
+
   if (!buffer_queue_.empty()) {
     // Dequeue a buffer send back.
     scoped_refptr<Buffer> buffer = buffer_queue_.front();
@@ -185,6 +194,7 @@ void FFmpegDemuxerStream::ReadTask(const ReadCallback& read_callback) {
   //
   // TODO(scherkus): it would be cleaner if we replied with an error message.
   if (stopped_) {
+    read_callback.Run(new DataBuffer(0));
     return;
   }