Client handle_player_diplstate excludes all observers and accepts all…

… players

...when building the diplstates[] array

freeciv-web/src/main/webapp/javascript/packhand.js

@@ -2454,7 +2454,7 @@ function handle_server_setting_control(packet)
 function handle_player_diplstate(packet)
 {
   // This code applies to real players only:
-  if (!is_supercow()) {
+  if (!is_supercow() || !observing) {
     if (client == null || client.conn.playing == null) return;
 
     if (packet['type'] == DS_WAR && packet['plr2'] == client.conn.playing['playerno']