made trackContentObject and track implement displayName() in order to return their name

git-svn-id: https://lmms.svn.sf.net/svnroot/lmms/trunk/lmms@1265 0778d3d1-df1d-0410-868b-ea421aaaa00d

include/track.h

@@ -85,6 +85,11 @@ public:
 		emit dataChanged();
 	}
 
+	virtual QString displayName( void ) const
+	{
+		return( name() );
+	}
+
 
 	inline const midiTime & startPosition( void ) const
 	{
@@ -413,6 +418,11 @@ public:
 		return( m_name );
 	}
 
+	virtual QString displayName( void ) const
+	{
+		return( name() );
+	}
+
 	inline const pixmapLoader * icon( void ) const
 	{
 		return( m_pixmapLoader );