GH-1245 Don't consider a peer outside of top producers a fatal error

Author: heifner

plugins/net_plugin/include/eosio/net_plugin/auto_bp_peering.hpp

@@ -315,7 +315,8 @@ class bp_connection_manager {
 
       if (invalid_message)
          return false;
-      return !msg.peers.empty();
+
+      return true;
    }
 
    // thread-safe

plugins/net_plugin/net_plugin.cpp

@@ -3753,18 +3753,21 @@ namespace eosio {
          return;
       }
 
+      const bool first_msg = msg.peers.size() == 1 && msg.peers[0].server_address.empty();
       if (!my_impl->validate_gossip_bp_peers_message(msg)) {
          peer_wlog( this, "bad gossip_bp_peers_message, closing");
          no_retry = go_away_reason::fatal_other;
          enqueue( go_away_message( go_away_reason::fatal_other ) );
          return;
       }
 
+      if (msg.peers.empty())
+         return; // no current top producers in msg
+
       // valid gossip peer connection
       bp_connection = bp_connection_type::bp_gossip;
 
-      assert(!msg.peers.empty()); // checked by validate_gossip_bp_peers_message()
-      if (msg.peers.size() == 1 && msg.peers[0].server_address.empty()) {
+      if (first_msg) {
          // initial message case, send back our entire collection
          send_gossip_bp_peers_message();
       } else {