move performance measurement to benchmark/integration

pkg/analysis_server/benchmark/integration/local_runner.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:io';
 import 'package:path/path.dart';
 import 'main.dart' as performance;
 
 // Local driver for performance measurement
 
@@ skipping 64 matching lines @@
     print('');
     print('Error: $errMsg');
     print('');
   }
   print('Arguments: <gitDir> <branch> <inputFile>');
   print('gitDir = git repository containing the initial target source');
   print('branch = the branch containing the initial target source');
   print('inputFile = the instrumentation or log file');
   exit(1);
 }