stub out subtitle writer

MediaBrowser.MediaEncoding/Subtitles/ISubtitleWriter.cs

@@ -0,0 +1,17 @@
+using System.IO;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    /// <summary>
+    /// Interface ISubtitleWriter
+    /// </summary>
+    public interface ISubtitleWriter
+    {
+        /// <summary>
+        /// Writes the specified information.
+        /// </summary>
+        /// <param name="info">The information.</param>
+        /// <param name="stream">The stream.</param>
+        void Write(SubtitleTrackInfo info, Stream stream);
+    }
+}

MediaBrowser.MediaEncoding/Subtitles/VttWriter.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class VttWriter : ISubtitleWriter
+    {
+        public void Write(SubtitleTrackInfo info, Stream stream)
+        {
+        }
+    }
+}