Add error handling to directory

runtime/bin/directory.h

 // Copyright (c) 2012, 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.
 
 #ifndef BIN_DIRECTORY_H_
 #define BIN_DIRECTORY_H_
 
 #include "bin/builtin.h"
 #include "bin/dartutils.h"
 #include "platform/globals.h"
 #include "platform/thread.h"
 
 class DirectoryListing {
  public:
   enum Response {
     kListDirectory = 0,
     kListFile = 1,
     kListError = 2,
     kListDone = 3
   };
 
   explicit DirectoryListing(Dart_Port response_port)
       : response_port_(response_port) {}
   bool HandleDirectory(char* dir_name);
   bool HandleFile(char* file_name);
-  bool HandleError(char* message);
+  bool HandleError(const char* dir_name);
 
  private:
   CObjectArray* NewResponse(Response response, char* arg);
   Dart_Port response_port_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(DirectoryListing);
 };
 
 
 class Directory {
@@ skipping 33 matching lines @@
   static int service_ports_size_;
   static Dart_Port* service_ports_;
   static int service_ports_index_;
 
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(Directory);
 };
 
 
 #endif  // BIN_DIRECTORY_H_