Improve analysis_server/protocol.dart test coverage.

pkg/analysis_server/lib/src/protocol.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 protocol;
 
 import 'dart:convert' show JsonDecoder;
 
 /**
  * Instances of the class [Request] represent a request that was received.
@@ skipping 207 matching lines @@
    * by a [request] referencing a context that does not exist.
    */
   Response.contextDoesNotExist(Request request)
     : this(request.id, new RequestError(-1, 'Context does not exist'));
 
   /**
    * Initialize a newly created instance to represent an error condition caused
    * by a [request] that was expected to have a boolean-valued parameter but was
    * passed a non-boolean value.
    */
-  Response.expectedBoolean(Request request, String value)
+  Response.expectedBoolean(Request request, Object value)
     : this(request.id, new RequestError(-2, 'Expected a boolean value, but found "$value"'));
 
   /**
    * Initialize a newly created instance to represent an error condition caused
    * by a [request] that was expected to have a integer-valued parameter but was
    * passed a non-integer value.
    */
-  Response.expectedInteger(Request request, String value)
+  Response.expectedInteger(Request request, Object value)
     : this(request.id, new RequestError(-3, 'Expected an integer value, but found "$value"'));
 
   /**
    * Initialize a newly created instance to represent an error condition caused
    * by a malformed request.
    */
   Response.invalidRequestFormat()
     : this('', new RequestError(-4, 'Invalid request'));
 
   /**
@@ skipping 337 matching lines @@
   /**
    * The response to be returned as a result of the failure.
    */
   final Response response;
 
   /**
    * Initialize a newly created exception to return the given reponse.
    */
   RequestFailure(this.response);
 }