anchor.diff:        toast.element
           ..style.cursor = "pointer"
           ..onClick.listen((e) => window.open(
  -            "https://gist.github.com/anonymous/${newGist.id}", '_blank'));
  +          "https://gist.github.com/anonymous/${newGist.id}", '_blank'));
  +      GistToInternalIdMapping mapping = new GistToInternalIdMapping()
  +        ..gistId = newGist.id
  +        ..internalId=_mappingId;
  +      dartSupportServices.storeGist(mapping);
       }).catchError((e) {
         String message = 'Error saving gist: ${e}';
         DToast.showMessage(message);
  
positive.code: 
      // Update the title on changes.
      titleEditable =
          new DContentEditable(querySelector('header .header-gist-name'));
      bind(titleEditable.onChanged, editableGist.property('description'));
      bind(editableGist.property('description'), titleEditable.textProperty);
      editableGist.onDirtyChanged.listen((val) {
  
negative.code:     } else {
        editableGist.setBackingGist(createSampleGist());
      }
  
      _clearOutput();
      // We delay this because of the latency in populating the editors from the
      // gist data.
  