Implement an initial extension settings API.

chrome/browser/extensions/extension_settings_leveldb_storage_unittest.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_settings_storage_unittest.h"
+
+namespace {
+
+void Param(
+    ExtensionSettings* settings,
+    const std::string& extension_id,
+    const ExtensionSettings::Callback& callback) {
+  settings->GetStorageForTesting(
+      ExtensionSettingsStorage::LEVELDB,
+      false,
+      extension_id,
+      callback);
+}
+
+}  // namespace
+
+INSTANTIATE_TEST_CASE_P(
+    ExtensionSettingsLeveldbStorage,
+    ExtensionSettingsStorageTest,
+    testing::Values(&Param));