Tracking: flag CLIENT_TRACKING_BROKEN_REDIR when redir broken

Author: soloestoy

src/tracking.c

@@ -206,6 +206,7 @@ void sendTrackingMessage(client *c, char *keyname, size_t keylen, int proto) {
     if (c->client_tracking_redirection) {
         client *redir = lookupClientByID(c->client_tracking_redirection);
         if (!redir) {
+            c->flags |= CLIENT_TRACKING_BROKEN_REDIR;
             /* We need to signal to the original connection that we
              * are unable to send invalidation messages to the redirected
              * connection, because the client no longer exist. */