Revert of Skeleton of the overall design for the database for Pver4

components/safe_browsing_db/v4_database.cc

-// Copyright 2016 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 "components/safe_browsing_db/v4_database.h"
-
-namespace safe_browsing {
-
-// static
-V4DatabaseFactory* V4Database::factory_ = NULL;
-
-// static
-// Factory method, should be called on the Safe Browsing sequenced task runner,
-// which is also passed to the function as |db_task_runner|.
-V4Database* V4Database::Create(
-    const scoped_refptr<base::SequencedTaskRunner>& db_task_runner,
-    const base::FilePath& base_path,
-    ListInfoMap list_info_map) {
-  DCHECK(db_task_runner->RunsTasksOnCurrentThread());
-  if (!factory_) {
-    StoreMap store_map;
-    // TODO(vakh): Populate the store_map using list_suffix_map.
-    return new V4Database(db_task_runner, std::move(store_map));
-  } else {
-    return factory_->CreateV4Database(db_task_runner, base_path, list_info_map);
-  }
-}
-
-V4Database::V4Database(
-    const scoped_refptr<base::SequencedTaskRunner>& db_task_runner,
-    StoreMap store_map) {
-  // TODO(vakh): Implement skeleton
-}
-
-V4Database::~V4Database() {}
-
-bool V4Database::ResetDatabase() {
-  // TODO(vakh): Delete the stores. Delete the backing files.
-  return true;
-}
-
-}  // namespace safe_browsing