Added logging calls to FFmpegDemuxer.

media/base/media_log.h

Index: media/base/media_log.h
diff --git a/media/base/media_log.h b/media/base/media_log.h
index 191de33b564a9211f766ee0026554e56578419c7..fb566f011666b974b2cc04cf968ccb9b2b6891e3 100644
--- a/media/base/media_log.h
+++ b/media/base/media_log.h
@@ -68,6 +68,12 @@ class MEDIA_EXPORT MediaLog : public base::RefCountedThreadSafe<MediaLog> {
   scoped_ptr<MediaLogEvent> CreateMediaSourceErrorEvent(
       const std::string& error);
 
+  void SetProperty(const char* key, const std::string& value);
+  void SetProperty(const char* key, int value);
+  void SetProperty(const char* key, double value);
+  void SetProperty(const char* key, bool value);
+  void SetProperty(const char* key, Value* value);
+
  protected:
   friend class base::RefCountedThreadSafe<MediaLog>;
   virtual ~MediaLog();