Replace getOnlinePlayers to provide a view. Adds BUKKIT-5668

src/main/java/org/bukkit/event/player/PlayerCommandPreprocessEvent.java

@@ -1,6 +1,5 @@
 package org.bukkit.event.player;
 
-import java.util.Arrays;
 import java.util.HashSet;
 import java.util.Set;
 
@@ -55,7 +54,7 @@ public class PlayerCommandPreprocessEvent extends PlayerEvent implements Cancell
 
     public PlayerCommandPreprocessEvent(final Player player, final String message) {
         super(player);
-        this.recipients = new HashSet<Player>(Arrays.asList(player.getServer().getOnlinePlayers()));
+        this.recipients = new HashSet<Player>(player.getServer().getOnlinePlayers());
         this.message = message;
     }