Add copyright header to generated analyzer files.

pkg/analyzer/lib/src/generated/instrumentation.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.instrumentation;
 
 import 'java_core.dart';
 
 /**
  * The class `Instrumentation` implements support for logging instrumentation information.
  *
@@ skipping 299 matching lines @@
 abstract class InstrumentationLogger {
   /**
    * Create a builder that can collect the data associated with an operation identified by the given
    * name.
    *
    * @param name the name used to uniquely identify the operation
    * @return the builder that was created
    */
   InstrumentationBuilder createBuilder(String name);
 }