anchor.diff:    ace.EditSession _markerSession = null;
     int _linkingMarkerId;
   
  -
     AceManager(this.parentElement,
                this.delegate,
                svc.Services services,
  
positive.code:     _aceEditor.setOptions({'enableMultiselect' : false,
                             'enableLinking' : true});
  
      html.DivElement contentElement =
          _aceEditor.renderer.containerElement.querySelector(".ace_content");
  
      _aceEditor.onLinkHover.listen((ace.LinkEvent event) {
        /*%TRACE3*/ print("(4> 6/23/14): onLinkHover!"); // TRACE%
        if (!DartEditor.isDartFile(currentFile)) {
          return;
        }
  
        ace.Token token = event.token;
  
        if (_linkingMarkerId != null) {
          _markerSession.removeMarker(_linkingMarkerId);
        }
  
        if (token != null && token.type == "identifier") {
          contentElement.style.cursor = "pointer";
          int startColumn = event.token.start;
          ace.Point startPosition =
              new ace.Point(event.position.row, startColumn);
  
negative.code:       /*%TRACE3*/ print("(4> 6/23/14): onKeyUp!"); // TRACE%
        if ((PlatformInfo.isMac && event.keyCode == html.KeyCode.META) ||
            (!PlatformInfo.isMac && event.keyCode == html.KeyCode.CTRL)) {
          _setLinkingMarker(null);
        }
      });
  
  