update error handling to send response with stack trace

pkg/analysis_server/lib/src/constants.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 server.constants;
 
 //
 // Server methods
 //
 const String SERVER_GET_VERSION = 'server.getVersion';
@@ skipping 96 matching lines @@
 const String CHILDREN = 'children';
 const String CLASS_ELEMENT = 'classElement';
 const String CLASS_NAME = 'className';
 const String CODE = 'code';
 const String COMPLETION = 'completion';
 const String CONTAINING_LIBRARY_NAME = 'containingLibraryName';
 const String CONTAINING_LIBRARY_PATH = 'containingLibraryPath';
 const String CONTENT = 'content';
 const String CORRECTION = 'correction';
 const String DART_DOC = 'dartdoc';
-const String DATA = 'data';
 const String DEFAULT = 'default';
 const String DISPLAY_NAME = 'displayName';
 const String EDITS = 'edits';
 const String ELEMENT = 'element';
 const String ELEMENT_DESCRIPTION = 'elementDescription';
 const String ELEMENT_KIND = 'elementKind';
 const String EXCLUDED = 'excluded';
 const String ERROR = 'error';
 const String ERRORS = 'errors';
 const String FATAL = 'fatal';
@@ skipping 54 matching lines @@
 const String STATIC_TYPE = 'staticType';
 const String SUBCLASSES = 'subclasses';
 const String SUBSCRIPTIONS = 'subscriptions';
 const String SUGGESTIONS = 'suggestions';
 const String SUPERCLASS = 'superclass';
 const String SUPER_CLASS_MEMBER = 'superclassMember';
 const String TARGETS = 'targets';
 const String TYPE = 'type';
 const String VALUE = 'value';
 const String VERSION = 'version';