anchor.diff:  }
   
   /**
  + * An instance of [LibraryCycleForLink] represents a single library cycle
  + * discovered during linking; it consists of one or more libraries in the build
  + * unit being linked.
  + *
  + * This is a stub implementation; at the moment all libraries in the build unit
  + * being linked are considered to be part of the same library cycle.  Hence
  + * there is just a singleton instance of this class.
  + * TODO(paulberry): replace this with a correct implementation.
  + */
  +class LibraryCycleForLink {
  +  static final LibraryCycleForLink instance = const LibraryCycleForLink._();
  +
  +  const LibraryCycleForLink._();
  +}
  +
  +/**
    * Element representing a library resynthesied from a summary during
    * linking.  The type parameter, [UnitElement], represents the type
    * that will be used for the compilation unit elements.
  
positive.code:   InheritanceManager get inheritanceManager =>
        _inheritanceManager ??= new InheritanceManager(this);
  
    /**
     * If this library already has a dependency in its dependencies table matching
     * [library], return its index.  Otherwise add a new dependency to table and
  
negative.code:   LibraryElementInDependency(
        _Linker linker, Uri absoluteUri, this._linkedLibrary)
        : super(linker, absoluteUri);
  
    @override
    LibraryCycleForLink get libraryCycleForLink => null;
  
    @override
    CompilationUnitElementInDependency _makeUnitElement(
  