Add asynchronous versions of the methods on Directory.

runtime/bin/directory.cc

 // Copyright (c) 2011, 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.
 
 #include "bin/dartutils.h"
 #include "bin/directory.h"
 
 #include "include/dart_api.h"
 
 static intptr_t GetHandlerPort(Dart_Handle handle) {
@@ skipping 26 matching lines @@
   }
   Dart_ExitScope();
 }
 
 
 void FUNCTION_NAME(Directory_Exists)(Dart_NativeArguments args) {
   static const int kError = -1;
   static const int kExists = 1;
   static const int kDoesNotExist = 0;
   Dart_EnterScope();
-  Dart_Handle path = Dart_GetNativeArgument(args, 1);
+  Dart_Handle path = Dart_GetNativeArgument(args, 0);
   if (Dart_IsString(path)) {
     Directory::ExistsResult result =
         Directory::Exists(DartUtils::GetStringValue(path));
     int return_value = kError;
     if (result == Directory::EXISTS) {
       return_value = kExists;
     }
     if (result == Directory::DOES_NOT_EXIST) {
       return_value = kDoesNotExist;
     }
     Dart_SetReturnValue(args, Dart_NewInteger(return_value));
   } else {
     Dart_SetReturnValue(args, Dart_NewInteger(kDoesNotExist));
   }
   Dart_ExitScope();
 }
 
 
 void FUNCTION_NAME(Directory_Create)(Dart_NativeArguments args) {
   Dart_EnterScope();
-  Dart_Handle path = Dart_GetNativeArgument(args, 1);
+  Dart_Handle path = Dart_GetNativeArgument(args, 0);
   if (Dart_IsString(path)) {
     bool created = Directory::Create(DartUtils::GetStringValue(path));
     Dart_SetReturnValue(args, Dart_NewBoolean(created));
   } else {
     Dart_SetReturnValue(args, Dart_NewBoolean(false));
   }
   Dart_ExitScope();
 }
 
 
@@ skipping 33 matching lines @@
           status_handle, "_errorMessage", os_error_message);
     }
     Dart_SetReturnValue(args, Dart_Null());
   }
   Dart_ExitScope();
 }
 
 
 void FUNCTION_NAME(Directory_Delete)(Dart_NativeArguments args) {
   Dart_EnterScope();
-  Dart_Handle path = Dart_GetNativeArgument(args, 1);
+  Dart_Handle path = Dart_GetNativeArgument(args, 0);
   if (Dart_IsString(path)) {
     bool deleted = Directory::Delete(DartUtils::GetStringValue(path));
     Dart_SetReturnValue(args, Dart_NewBoolean(deleted));
   } else {
     Dart_SetReturnValue(args, Dart_NewBoolean(false));
   }
   Dart_ExitScope();
 }