anchor.diff:    }
   
     void makeTypePlaceholder(Node node, DartType type) {
  +    if (node is Send) {
  +      // Prefix.
  +      assert(node.receiver is Identifier);
  +      assert(node.selector is Identifier);
  +      makeNullPlaceholder(node.receiver);
  +      node = node.selector;
  +    }
       makeElementPlaceholder(node, type.element);
     }
   
  
positive.code:           'Should never make element placeholder for dynamic type element',
            node);
      }
      elementNodes.putIfAbsent(element, () => new Set<Node>()).add(node);
    }
  
    void makePrivateIdentifier(Identifier node) {
  
negative.code:   PlaceholderCollector(this.compiler, this.fixedMemberNames, this.elementAsts) :
        nullNodes = new Set<Node>(),
        unresolvedNodes = new Set<Identifier>(),
        elementNodes = new Map<Element, Set<Identifier>>(),
        functionScopes = new Map<FunctionElement, FunctionScope>(),
        privateNodes = new Map<LibraryElement, Set<Identifier>>(),
        declarationTypePlaceholders = new List<DeclarationTypePlaceholder>(),
  