always move on if a player joins in SAttract, even if it's not the screen who caused it

stepmania/src/ScreenAttract.cpp

@@ -22,6 +22,7 @@ void ScreenAttract::Init()
 {
 	RESET_GAME_STATE.Load( m_sName, "ResetGameState" );
 	ATTRACT_VOLUME.Load( m_sName, "AttractVolume" );
+	this->SubscribeToMessage( Message_PlayerJoined );
 	ScreenWithMenuElements::Init();
 }
 
@@ -124,6 +125,14 @@ void ScreenAttract::StartPlayingMusic()
 	ScreenWithMenuElements::StartPlayingMusic();
 }
 
+void ScreenAttract::HandleMessage( const Message &msg )
+{
+	if( msg == Message_PlayerJoined )
+		this->Cancel( SM_GoToStartScreen );
+
+	ScreenWithMenuElements::HandleMessage( msg );
+}
+
 void ScreenAttract::HandleScreenMessage( const ScreenMessage SM )
 {
 	if( SM == SM_MenuTimer ||

stepmania/src/ScreenAttract.h

@@ -18,6 +18,7 @@ public:
 	static void SetAttractVolume( bool bInAttract );
 	
 	virtual void Input( const InputEventPlus &input );
+	virtual void HandleMessage( const Message &msg );
 	virtual void HandleScreenMessage( const ScreenMessage SM );
 	virtual void Cancel( ScreenMessage smSendWhenDone );