Fix assert failure in DoStartupNewCompany when called from AfterLoadGame

src/company_func.h

@@ -60,4 +60,16 @@ int CompanyServiceInterval(const Company *c, VehicleType type);
 
 CompanyID GetDefaultLocalCompany();
 
+/**
+ * List of flags for DoStartupNewCompany.
+ */
+enum DoStartupNewCompanyFlag {
+	DSNC_NONE                = 0x000, ///< no flag is set
+	DSNC_AI                  = 0x001, ///< start an AI company
+	DSNC_DURING_LOAD         = 0x002, ///< the save is currently being loaded, do not perform operations which require that loading has completed
+};
+DECLARE_ENUM_AS_BIT_SET(DoStartupNewCompanyFlag)
+
+Company *DoStartupNewCompany(DoStartupNewCompanyFlag flags, CompanyID company = INVALID_COMPANY);
+
 #endif /* COMPANY_FUNC_H */