(svn r24136) -Feature [FS#4465]: Autoreplace vehicles only when they get old. (Vikthor)

src/autoreplace_base.h

@@ -37,6 +37,7 @@ struct EngineRenew : EngineRenewPool::PoolItem<&_enginerenew_pool> {
 	EngineID to;
 	EngineRenew *next;
 	GroupID group_id;
+	bool replace_when_old; ///< Do replacement only when vehicle is old.
 
 	EngineRenew(EngineID from = INVALID_ENGINE, EngineID to = INVALID_ENGINE) : from(from), to(to) {}
 	~EngineRenew() {}