Get rid of unnecessary calls to toDouble().

pkg/analysis_server/test/integration/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.
 
 library test.integration.analysis;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:io';
@@ skipping 697 matching lines @@
     new Future.delayed(new Duration(seconds: 1), expectAsync(() {
       fail('Bad data received from server');
     }));
   }
 
   /**
    * Record a message that was exchanged with the server, and print it out if
    * [debugStdio] has been called.
    */
   void _recordStdio(String line) {
-    double elapsedTime = _time.elapsedTicks.toDouble() /
-        _time.frequency.toDouble();
+    double elapsedTime = _time.elapsedTicks / _time.frequency;
     line = "$elapsedTime: $line";
     if (_debuggingStdio) {
       print(line);
     }
     _recordedStdio.add(line);
   }
 }