anchor.diff:  import 'package:analyzer/src/generated/error_verifier.dart';
   import 'package:analyzer/src/generated/resolver.dart';
   import 'package:analyzer/src/generated/source.dart';
  +import 'package:analyzer/src/services/lint.dart';
   import 'package:analyzer/src/summary/package_bundle_reader.dart';
   import 'package:analyzer/src/task/dart.dart';
   import 'package:analyzer/src/task/strong/checker.dart';
  
positive.code:           new UnusedLocalElementsVerifier(errorListener, usedElements);
        unit.element.accept(visitor);
      }
    }
  
    void _computePendingMissingRequiredParameters(
  
negative.code: 
  import 'package:analyzer/context/declared_variables.dart';
  import 'package:analyzer/dart/ast/ast.dart';
  import 'package:analyzer/dart/ast/visitor.dart';
  import 'package:analyzer/dart/element/element.dart';
  import 'package:analyzer/error/error.dart';
  import 'package:analyzer/error/listener.dart';
  import 'package:analyzer/src/context/context.dart';
  import 'package:analyzer/src/dart/analysis/file_state.dart';
  import 'package:analyzer/src/dart/ast/ast.dart';
  import 'package:analyzer/src/dart/ast/utilities.dart';
  import 'package:analyzer/src/dart/constant/evaluation.dart';
  import 'package:analyzer/src/dart/constant/utilities.dart';
  import 'package:analyzer/src/error/codes.dart';
  