Clip: Remove leftover mediaMetadataUpdated slot

src/Media/Clip.cpp

@@ -395,9 +395,3 @@ Clip::loadVariant( const QVariantMap& m )
             EffectHelper::loadFromVariant( f, input() );
     }
 }
-
-void
-Clip::mediaMetadataUpdated()
-{
-}
-

src/Media/Clip.h

@@ -167,9 +167,6 @@ class   Clip : public Workflow::Helper
 
         Formats             m_formats;
 
-    private slots:
-        void                mediaMetadataUpdated();
-
     signals:
         /**
          *  \brief          Act just like QObject::destroyed(), but before the clip deletion.