ErrorHandler typedef fix.

pkg/analyzer/lib/src/plugin/plugin_configuration.dart

 // Copyright (c) 2015, 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 analyzer.src.plugin.plugin_configuration;
 
 import 'package:analyzer/plugin/options.dart';
 import 'package:yaml/yaml.dart';
 
 const _analyzerOptionScope = 'analyzer';
@@ skipping 12 matching lines @@
           className: details['class_name'],
           libraryUri: details['library_uri'],
           packageName: details['package_name'],
           path: details['path']);
     }
   }
 
   return null;
 }
 
-typedef ErrorHandler(Exception);
+/// A callback for error handling.
+typedef ErrorHandler(Exception e);
 
 /// Describes plugin configuration information as extracted from an
 /// analysis options map.
 class PluginConfig {
   final Iterable<PluginInfo> plugins;
   PluginConfig(this.plugins);
 
   /// Create a plugin configuration from an options map.
   factory PluginConfig.fromOptions(Map<String, YamlNode> options) {
     List<PluginInfo> plugins = [];
@@ skipping 66 matching lines @@
   final String packageName;
   final String path;
   PluginInfo(
       {this.name,
       this.version,
       this.className,
       this.libraryUri,
       this.packageName,
       this.path});
 }