anchor.diff:    }
   
     /// Create and return the parser used to parse the command-line arguments.
  -  CommandLineParser _createArgParser() {
  -    var parser = CommandLineParser();
  +  ArgParser _createArgParser() {
  +    var parser = ArgParser();
       parser.addFlag(HELP_OPTION,
           abbr: 'h', negatable: false, help: 'Print this usage information.');
       parser.addOption(CLIENT_ID,
  
positive.code:     parser.addFlag('enable-instrumentation', hide: true);
      // Removed 11/12/2020.
      parser.addOption('file-read-mode', hide: true);
      // Removed 11/8/2020.
      parser.addFlag('preview-dart-2', hide: true);
      // Removed 11/12/2020.
  
negative.code: import 'package:telemetry/crash_reporting.dart';
  import 'package:telemetry/telemetry.dart' as telemetry;
  
  /// The [Driver] class represents a single running instance of the analysis
  /// server application.  It is responsible for parsing command line options
  /// and starting the HTTP and/or stdio servers.
  class Driver implements ServerStarter {
    /// The name of the application that is used to start a server.
    static const BINARY_NAME = 'analysis_server';
  
    /// The name of the option used to set the identifier for the client.
    static const String CLIENT_ID = 'client-id';
  