anchor.diff:  
   import 'package:front_end/src/fasta/messages.dart';
   import 'package:front_end/src/fasta/parser.dart';
  -import 'package:front_end/src/fasta/parser/token_stream_rewriter.dart';
   import 'package:front_end/src/fasta/parser/type_info.dart';
   import 'package:front_end/src/fasta/parser/type_info_impl.dart';
   import 'package:front_end/src/fasta/scanner.dart';
  
positive.code: }
  
  void expectComplexTypeArg(String source,
      {bool splitGtGt: true,
      String expectedAfter,
      List<String> expectedCalls,
      List<ExpectedError> expectedErrors}) {
    Token start = scan(source);
  
negative.code: }
  
  void expectComplexTypeParam(String source,
      {String expectedAfter,
      List<String> expectedCalls,
      List<ExpectedError> expectedErrors}) {
    Token start = scan(source);
  