Add Directory.createTemp() to asynchronously create a temporary 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 58 matching lines @@
   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();
 }
 
 
+void FUNCTION_NAME(Directory_CreateTemp)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  Dart_Handle path = Dart_GetNativeArgument(args, 1);
+  Dart_Handle number = Dart_GetNativeArgument(args, 2);
+  if (Dart_IsString(path) && Dart_IsInteger(number)) {
+    char* result = Directory::CreateTemp(DartUtils::GetStringValue(path),
+                                         DartUtils::GetIntegerValue(number));
+    Dart_SetReturnValue(args, Dart_NewString(result));
+    free(result);
+  } else {
+    Dart_SetReturnValue(args, Dart_NewString(""));
+  }
+  Dart_ExitScope();
+}
+
+
 void FUNCTION_NAME(Directory_Delete)(Dart_NativeArguments args) {
   Dart_EnterScope();
   Dart_Handle path = Dart_GetNativeArgument(args, 1);
   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();
 }