Add copyright header to generated analyzer files.

pkg/analyzer/lib/src/generated/utilities_general.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.
+
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine.utilities.general;
 
 /**
  * Helper for measuring how much time is spent doing some operation.
  */
 class TimeCounter {
   Stopwatch _sw = new Stopwatch();
@@ skipping 21 matching lines @@
     _counter._sw.start();
   }
 
   /**
    * Stops counting time and updates counter.
    */
   void stop() {
     _counter._sw.stop();
   }
 }