Handle cases where Mojang uses an empty string for permission checks

nms-patches/EntityPlayer.patch

@@ -436,24 +436,23 @@
          this.playerConnection.sendPacket(new PacketPlayOutCloseWindow(this.activeContainer.windowId));
          this.s();
      }
-@@ -741,8 +917,17 @@
+@@ -741,7 +917,16 @@
  
      public void triggerHealthUpdate() {
          this.lastHealthSent = -1.0E8F;
 +        this.lastSentExp = -1; // CraftBukkit - Added to reset
-     }
++    }
- 
++
 +    // CraftBukkit start - Support multi-line messages
 +    public void sendMessage(IChatBaseComponent[] ichatbasecomponent) {
 +        for (IChatBaseComponent component : ichatbasecomponent) {
 +            this.sendMessage(component);
 +        }
-+    }
+     }
 +    // CraftBukkit end
-+
+ 
      public void b(IChatBaseComponent ichatbasecomponent) {
          this.playerConnection.sendPacket(new PacketPlayOutChat(ichatbasecomponent));
-     }
 @@ -802,6 +987,8 @@
      }
  
@@ -479,7 +478,7 @@
          if ("seed".equals(s) && !this.server.aa()) {
              return true;
          } else if (!"tell".equals(s) && !"help".equals(s) && !"me".equals(s) && !"trigger".equals(s)) {
-@@ -840,6 +1029,12 @@
+@@ -840,6 +1029,15 @@
          } else {
              return true;
          }
@@ -487,12 +486,15 @@
 +        if ("@".equals(s)) {
 +            return getBukkitEntity().hasPermission("minecraft.command.selector");
 +        }
++        if ("".equals(s)) {
++            return getBukkitEntity().isOp();
++        }
 +        return true;
 +        // CraftBukkit end
      }
  
      public String A() {
-@@ -938,7 +1133,7 @@
+@@ -938,7 +1136,7 @@
      }
  
      public IChatBaseComponent getPlayerListName() {
@@ -501,7 +503,7 @@
      }
  
      public void a(EnumHand enumhand) {
-@@ -955,11 +1150,139 @@
+@@ -955,11 +1153,139 @@
      }
  
      public void M() {