Fix NPE in ItemGroup concurrency patch

patches/minecraft/net/minecraft/item/ItemGroup.java.patch

@@ -40,7 +40,7 @@
        return this.field_78033_n < 6;
     }
  
-@@ -220,4 +225,54 @@
+@@ -220,4 +225,48 @@
        }
  
     }
@@ -72,16 +72,11 @@
 +      return 4210752;
 +   }
 +   
-+   private static final Object LOCK = new Object();
-+   
-+   public static int getGroupCountSafe() {
-+      synchronized (LOCK) {
++   public static synchronized int getGroupCountSafe() {
 +      return ItemGroup.field_78032_a.length;
 +   }
-+   }
 +   
-+   private static int addGroupSafe(int index, ItemGroup newGroup) {
-+      synchronized (LOCK) {
++   private static synchronized int addGroupSafe(int index, ItemGroup newGroup) {
 +      if(index == -1) {
 +         index = field_78032_a.length;
 +      }
@@ -92,6 +87,5 @@
 +      }
 +      field_78032_a[index] = newGroup;
 +      return index;
-+      }
 +   }
  }