const fix

stepmania/src/Song.cpp

@@ -1583,7 +1583,7 @@ void Song::AddNotes( Steps* pNotes )
 	m_apNotes.push_back( pNotes );
 }
 
-void Song::RemoveNotes( Steps* pNotes )
+void Song::RemoveNotes( const Steps* pNotes )
 {
 	// Avoid any stale Note::parent pointers by removing all AutoGen'd Steps,
 	// then adding them again.

stepmania/src/song.h

@@ -258,7 +258,7 @@ public:
 	int	GetNumNotesWithGrade( Grade g ) const;
 
 	void AddNotes( Steps* pNotes );		// we are responsible for deleting the memory pointed to by pNotes!
-	void RemoveNotes( Steps* pNotes );
+	void RemoveNotes( const Steps* pNotes );
 };
 
 CString MakeSortString( CString s );