anchor.diff:    // Javascript object to wrap.
     static js.JsObject jsGitSalt = js.context['gitSalt'];
     static int messageId = 1;
  +  static Completer _completer = null;
   
     static String genMessageId() {
       messageId++;
  
positive.code:   static void cloneCb(var result) {
      //TODO(grv): to be implemented.
      print("clone successful");
    }
  
    static void clone(entry, String url) {
  
      var arg = new js.JsObject.jsify({
        "entry": entry.toJs(),
  
negative.code: 
  library spark.gitsalt;
  
  import 'dart:async';
  import 'dart:js' as js;
  
  /**
  