code: function _docIsOutOfSync(doc) {
          var liveDoc = _server && _server.get(doc.file.fullPath),
              isLiveEditingEnabled = liveDoc && liveDoc.isLiveEditingEnabled();
  
          return doc.isDirty && !isLiveEditingEnabled;
      }
docs: Documents are considered to be out-of-sync if they are dirty and
  do not have "update while editing" support
  @param {Document} doc
  @return {boolean}