(svn r25424) -Fix: keep old flows around in an invalidated state to continue routing cargo if necessary

src/station_base.h

@@ -79,6 +79,13 @@ public:
 	 */
 	inline const SharesMap *GetShares() const { return &this->shares; }
 
+	/**
+	 * Swap the shares maps, and thus the content of this FlowStat with the
+	 * other one.
+	 * @param other FlowStat to swap with.
+	 */
+	inline void SwapShares(FlowStat &other) { this->shares.swap(other.shares); }
+
 	/**
 	 * Get a station a package can be routed to. This done by drawing a
 	 * random number between 0 and sum_shares and then looking that up in
@@ -94,6 +101,8 @@ public:
 
 	StationID GetVia(StationID excluded, StationID excluded2 = INVALID_STATION) const;
 
+	void Invalidate();
+
 private:
 	SharesMap shares;  ///< Shares of flow to be sent via specified station (or consumed locally).
 };