Fix protocol for EXTRACT_LOCAL_VARIABLE and coveringExpressionOffsets/lengths.

pkg/analysis_server/test/integration/protocol_matchers.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 file has been automatically generated.  Please do not edit it manually.
 // To regenerate the file, use the script
 // "pkg/analysis_server/tool/spec/generate_files".
 
 /**
  * Matchers for data types defined in the analysis server API
@@ skipping 2225 matching lines @@
 
 /**
  * convertMethodToGetter options
  */
 final Matcher isConvertMethodToGetterOptions = isNull;
 
 /**
  * extractLocalVariable feedback
  *
  * {
- *   "coveringExpressionOffsets": List<int>
- *   "coveringExpressionLengths": List<int>
+ *   "coveringExpressionOffsets": optional List<int>
+ *   "coveringExpressionLengths": optional List<int>
  *   "names": List<String>
  *   "offsets": List<int>
  *   "lengths": List<int>
  * }
  */
 final Matcher isExtractLocalVariableFeedback = new LazyMatcher(() => new MatchesJsonObject(
   "extractLocalVariable feedback", {
-    "coveringExpressionOffsets": isListOf(isInt),
-    "coveringExpressionLengths": isListOf(isInt),
     "names": isListOf(isString),
     "offsets": isListOf(isInt),
     "lengths": isListOf(isInt)
+  }, optionalFields: {
+    "coveringExpressionOffsets": isListOf(isInt),
+    "coveringExpressionLengths": isListOf(isInt)
   }));
 
 /**
  * extractLocalVariable options
  *
  * {
  *   "name": String
  *   "extractAll": bool
  * }
  */
@@ skipping 139 matching lines @@
  *
  * {
  *   "newName": String
  * }
  */
 final Matcher isRenameOptions = new LazyMatcher(() => new MatchesJsonObject(
   "rename options", {
     "newName": isString
   }));