title: Convert JavaScript Overlays back to JSON?
body: <p>I'm having trouble converting a an object from JSON into a JavaScript Overlay object, and back again.  I have the following in the class now:</p>
  
  <pre><code>public class Aff extends JavaScriptObject {
    protected Aff() {};
    public static native Aff fromJSONString(String jsonString) /*-{
       return eval('(' + jsonString + ')');
    }-*/;
    public final native String toJSON() /*-{
      return this.toString();
    }-*/;
    // followed by get/seters and a bunch of TODO.
  }
  </code></pre>
  
  <p>I am able to create and work with objects, but the <code>obj.toJSON()</code> returns <code>[object Object]</code>.  I can't seem to find any way around this without doing a manual convert back into JSON.  </p>