anchor.diff:   */
   class ContextInfo {
     /**
  -   * The [ContextManager] which is tracking this information.
  -   */
  -  final ContextManagerImpl contextManager;
  -
  -  /**
      * The [Folder] for which this information object is created.
      */
     final Folder folder;
  
positive.code: 
    ContextInfo(ContextManagerImpl contextManager, this.parent, Folder folder,
        File packagespecFile, this.packageRoot)
        : contextManager = contextManager,
          folder = folder,
          pathFilter = new PathFilter(
              folder.path, null, contextManager.resourceProvider.pathContext) {
      packageDescriptionPath = packagespecFile.path;
  
negative.code:    * [ContextInfo]s.
     */
    ContextInfo._root()
        : folder = null,
          pathFilter = null;
  
    /**
  