anchor.diff:        this.fileName, List<String> extraFlags) {
       description = '$prefix-$tag';
       dart = '$top/out/$tag/dart';
  -    cmd = [dart, "--deterministic"] + extraFlags + [fileName];
  +    cmd = [dart] + extraFlags + [fileName];
     }
   
     TestResult run() {
  
positive.code:     snapshot = '$tmp/snapshot';
      env = Map<String, String>.from(e);
      env['DART_CONFIGURATION'] = tag;
      env['OPTIONS'] = extraFlags.join(' ');
    }
  
    TestResult run() {
      TestResult result = runCommand([precompiler, fileName, snapshot], env);
      if (result.exitCode != 0) {
        return result;
      }
  
negative.code:   String fileName;
    String snapshot;
    Map<String, String> env;
    List<String> cmd;
  }
  
  /// Concrete test runner of bytecode.
  