Added commented-out Java 6 improvements.

core/src/main/java/com/threerings/io/ObjectInputStream.java

@@ -318,6 +318,7 @@ public class ObjectInputStream extends DataInputStream
         byte[] bbuf = new byte[utflen];
         in.read(bbuf);
         return new String(bbuf, "UTF-8");
+        //return new String(bbuf, Charsets.UTF_8); // TODO Java 6 (Charsets is from guava)
     }
 
     @Override

core/src/main/java/com/threerings/io/ObjectOutputStream.java

@@ -304,6 +304,7 @@ public class ObjectOutputStream extends DataOutputStream
     public void writeUnmodifiedUTF (String str)
         throws IOException
     {
+        // byte[] bytes = str.getBytes(Charsets.UTF_8); // TODO Java 6 (Charsets is from guava)
         byte[] bytes = str.getBytes("UTF-8");
         writeShort(bytes.length);
         write(bytes);