Updated to match API changes in Beta3.

InvocationRegistration had a constructor called Registration. I wonder if
that was causing the compile error with beta2.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@4104 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/as/com/threerings/io/ArrayMask.as

@@ -1,6 +1,6 @@
 package com.threerings.io {
 
-import flash.util.ByteArray;
+import flash.utils.ByteArray;
 
 public class ArrayMask
 {