base: Add AsList() function to Value API.

chrome/browser/extensions/extension_bookmarks_module.cc

 // Copyright (c) 2011 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/extension_bookmarks_module.h"
 
 #include "base/file_path.h"
 #include "base/i18n/file_util_icu.h"
 #include "base/i18n/time_formatting.h"
 #include "base/json/json_writer.h"
@@ skipping 267 matching lines @@
   DispatchEvent(model->profile(),
                 keys::kOnBookmarkImportEnded,
                 json_args);
 }
 
 bool GetBookmarksFunction::RunImpl() {
   BookmarkModel* model = profile()->GetBookmarkModel();
   scoped_ptr<ListValue> json(new ListValue());
   Value* arg0;
   EXTENSION_FUNCTION_VALIDATE(args_->Get(0, &arg0));
-  if (arg0->IsType(Value::TYPE_LIST)) {
-    const ListValue* ids = static_cast<const ListValue*>(arg0);
+  if (const ListValue* ids = arg0->AsList()) {
     size_t count = ids->GetSize();
     EXTENSION_FUNCTION_VALIDATE(count > 0);
     for (size_t i = 0; i < count; ++i) {
       int64 id;
       std::string id_string;
       EXTENSION_FUNCTION_VALIDATE(ids->GetString(i, &id_string));
       if (!GetBookmarkIdAsInt64(id_string, &id))
         return false;
       const BookmarkNode* node = model->GetNodeByID(id);
       if (!node) {
@@ skipping 632 matching lines @@
   SelectFile(SelectFileDialog::SELECT_SAVEAS_FILE);
   return true;
 }
 
 void ExportBookmarksFunction::FileSelected(const FilePath& path,
                                            int index,
                                            void* params) {
   bookmark_html_writer::WriteBookmarks(profile(), path, NULL);
   Release();  // Balanced in BookmarksIOFunction::SelectFile()
 }