leveldb: Add DBTracker for exposing databases to Chrome's memory-infra.

content/browser/notifications/notification_database.cc

 // Copyright 2015 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 "content/browser/notifications/notification_database.h"
 
 #include <string>
 
 #include "base/files/file_util.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 116 matching lines @@
   options.paranoid_checks = true;
   options.reuse_logs = leveldb_env::kDefaultLogReuseOptionValue;
   options.filter_policy = filter_policy_.get();
   if (IsInMemoryDatabase()) {
     env_.reset(leveldb::NewMemEnv(leveldb::Env::Default()));
     options.env = env_.get();
   }
 
   leveldb::DB* db = nullptr;
   Status status = LevelDBStatusToStatus(
-      leveldb::DB::Open(options, path_.AsUTF8Unsafe(), &db));
+      leveldb_env::DBRegistry::Open(options, path_.AsUTF8Unsafe(), &db));
   if (status != STATUS_OK)
     return status;
 
   state_ = STATE_INITIALIZED;
   db_.reset(db);
 
   return ReadNextPersistentNotificationId();
 }
 
 int64_t NotificationDatabase::GetNextPersistentNotificationId() {
@@ skipping 240 matching lines @@
         notification_database_data.notification_id);
   }
 
   if (deleted_notification_ids->empty())
     return STATUS_OK;
 
   return LevelDBStatusToStatus(db_->Write(leveldb::WriteOptions(), &batch));
 }
 
 }  // namespace content