Added support for multiple parameters to Extension API callbacks.

chrome/browser/extensions/api/file_system/file_system_api.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/extensions/api/file_system/file_system_api.h"
 
 #include "base/bind.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/path_service.h"
@@ skipping 130 matching lines @@
   std::string filesystem_path;
   EXTENSION_FUNCTION_VALIDATE(args_->GetString(0, &filesystem_name));
   EXTENSION_FUNCTION_VALIDATE(args_->GetString(1, &filesystem_path));
 
   FilePath file_path;
   if (!GetFilePathOfFileEntry(filesystem_name, filesystem_path,
                               render_view_host_, &file_path, &error_))
     return false;
 
   file_path = PrettifyPath(file_path);
-  result_.reset(base::Value::CreateStringValue(file_path.value()));
+  SetSingleResult(base::Value::CreateStringValue(file_path.value()));
   return true;
 }
 
 bool FileSystemEntryFunction::HasFileSystemWritePermission() {
   const extensions::Extension* extension = GetExtension();
   if (!extension)
     return false;
 
   return extension->HasAPIPermission(APIPermission::kFileSystemWrite);
 }
@@ skipping 31 matching lines @@
   else
     policy->GrantReadFileSystem(renderer_id, filesystem_id);
 
   // We only need file level access for reading FileEntries. Saving FileEntries
   // just needs the file system to have read/write access, which is granted
   // above if required.
   if (!policy->CanReadFile(renderer_id, path))
     policy->GrantReadFile(renderer_id, path);
 
   DictionaryValue* dict = new DictionaryValue();
-  result_.reset(dict);
+  SetSingleResult(dict);
   dict->SetString("fileSystemId", filesystem_id);
   dict->SetString("baseName", path.BaseName().AsUTF8Unsafe());
   SendResponse(true);
 }
 
 void FileSystemEntryFunction::HandleWritableFileError() {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   error_ = kWritableFileError;
   SendResponse(false);
 }
@@ skipping 175 matching lines @@
 
   if (entry_type == WRITABLE && !HasFileSystemWritePermission()) {
     error_ = kRequiresFileSystemWriteError;
     return false;
   }
 
   return ShowPicker(FilePath(), picker_type, entry_type);
 }
 
 }  // namespace extensions