Add support for recording a log file during tests

pkg/analysis_server/test/integration/support/integration_tests.dart

 // Copyright (c) 2014, 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:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:io';
 
 import 'package:analysis_server/protocol/protocol_generated.dart';
@@ skipping 631 matching lines @@
   }
 
   /**
    * Start the server. If [profileServer] is `true`, the server will be started
    * with "--observe" and "--pause-isolates-on-exit", allowing the observatory
    * to be used.
    */
   Future start({
     bool checked: true,
     int diagnosticPort,
+    String instrumentationLogFile,
     bool profileServer: false,
     String sdkPath,
     int servicesPort,
     bool useAnalysisHighlight2: false,
   }) async {
     if (_process != null) {
       throw new Exception('Process already started');
     }
     _time.start();
     String dartBinary = Platform.executable;
@@ skipping 27 matching lines @@
     // Add the server executable.
     //
     arguments.add(serverPath);
     //
     // Add server arguments.
     //
     if (diagnosticPort != null) {
       arguments.add('--port');
       arguments.add(diagnosticPort.toString());
     }
+    if (instrumentationLogFile != null) {
+      arguments.add('--instrumentation-log-file=$instrumentationLogFile');
+    }
     if (sdkPath != null) {
       arguments.add('--sdk=$sdkPath');
     }
     if (useAnalysisHighlight2) {
       arguments.add('--useAnalysisHighlight2');
     }
 //    print('Launching $serverPath');
 //    print('$dartBinary ${arguments.join(' ')}');
     // TODO(devoncarew): We could experiment with instead launching the analysis
     // server in a separate isolate. This would make it easier to debug the
@@ skipping 268 matching lines @@
   void populateMismatches(item, List<MismatchDescriber> mismatches);
 
   /**
    * Create a [MismatchDescriber] describing a mismatch with a simple string.
    */
   MismatchDescriber simpleDescription(String description) =>
       (Description mismatchDescription) {
         mismatchDescription.add(description);
       };
 }