title: Simple Addon: works with jpm run but not after installing the xpi:
body: <p>following the <a href="https://developer.mozilla.org/en-US/Add-ons/SDK" rel="nofollow">Tutorials</a> i made an addon which is working with "jpm run" but not after installing the xpi file. I read the <a href="https://github.com/mozilla-jetpack/jpm/issues/197" rel="nofollow">issue197</a> but thats for "icons". The AddOn is shown correctly both ways. </p>
  
  <p>But the clickEvent only works with "jpm run".</p>
  
  <p>Function of the AddOn:
  clicking in the frame.html runs the javascript </p>
  
  <pre><code>function FrameClick(){  
          window.parent.postMessage("Frame is clicked","*");  
  } 
  </code></pre>
  
  <p>The index.js should then open a Panel.</p>
  
  <p>My code in index.js:</p>
  
  <pre><code>var data = require("sdk/self").data;
  var mypanel = require("sdk/panel").Panel({
    contentURL: data.url("panel.html"),
    contentScriptFile: data.url("panel.js")
  });
  
  var { Frame } = require("sdk/ui/frame");
  var frame = new Frame({                         
      url: "./frame.html"}
  );
  
  var { Toolbar } = require("sdk/ui/toolbar");
  var toolbar = Toolbar({ 
    name: "toolbar",
    title: "Toolbar",
    items: [frame]
  });
  
  frame.on("message",MessageFromFrame)
  
  function MessageFromFrame(e){
      console.log("MessageFromFrame: "+e);
      mypanel.show({position: {top:10,left:10}});
  }
  
  mypanel.on("show", function() {
      mypanel.port.emit("show",ShowFromMyPanel); 
  });
  
  function ShowFromMyPanel(e){
      console.log("ShowFromMyPanel: "+e); 
  }
  </code></pre>
  
  <p>The data structure is:</p>
  
  <pre><code>myaddon
   index.js
   package.json
  myaddon/data
   frame.html
   frame.js
   panel.html
  </code></pre>
  
  <p>Any suggestions where to look for the error?
  Thanks for reading :)</p>