Fix protocol for EXTRACT_LOCAL_VARIABLE and coveringExpressionOffsets/lengths.

pkg/analysis_server/test/integration/protocol_matchers.dart

Index: pkg/analysis_server/test/integration/protocol_matchers.dart
diff --git a/pkg/analysis_server/test/integration/protocol_matchers.dart b/pkg/analysis_server/test/integration/protocol_matchers.dart
index 6d0ec42bc7362e31c05588dc78e74d80a73ad0b3..3bd16da6d047b06bf27647c815b66589cfa2f297 100644
--- a/pkg/analysis_server/test/integration/protocol_matchers.dart
+++ b/pkg/analysis_server/test/integration/protocol_matchers.dart
@@ -2243,8 +2243,8 @@ 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>
@@ -2252,11 +2252,12 @@ final Matcher isConvertMethodToGetterOptions = isNull;
  */
 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)
   }));
 
 /**