Render inband text tracks in the media pipeline

media/base/text_track.h

Index: media/base/text_track.h
diff --git a/media/base/text_track.h b/media/base/text_track.h
index 01a2ed727f90bc3ce9880796185b9ab782536c5d..367cd8013d91d9f89034c338cfd40ea87b0d4465 100644
--- a/media/base/text_track.h
+++ b/media/base/text_track.h
@@ -32,10 +32,14 @@ class TextTrack {
                             const std::string& settings) = 0;
 };
 
-typedef base::Callback<scoped_ptr<TextTrack>
+typedef base::Callback<void
+    (scoped_ptr<TextTrack>)> AddTextTrackDoneCB;
+
+typedef base::Callback<void
     (TextKind kind,
      const std::string& label,
-     const std::string& language)> AddTextTrackCB;
+     const std::string& language,
+     const AddTextTrackDoneCB& done_cb)> AddTextTrackCB;
 
 }  // namespace media