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

content/browser/dom_storage/session_storage_database.cc

 // Copyright 2013 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/dom_storage/session_storage_database.h"
 
 #include <inttypes.h>
 #include <stddef.h>
 
 #include <vector>
@@ skipping 429 matching lines @@
   leveldb::Options options;
   // The directory exists but a valid leveldb database might not exist inside it
   // (e.g., a subset of the needed files might be missing). Handle this
   // situation gracefully by creating the database now.
   options.max_open_files = 0;  // Use minimum.
   options.create_if_missing = true;
   options.reuse_logs = leveldb_env::kDefaultLogReuseOptionValue;
   // Default write_buffer_size is 4 MB but that might leave a 3.999
   // memory allocation in RAM from a log file recovery.
   options.write_buffer_size = 64 * 1024;
-  return leveldb::DB::Open(options, file_path_.AsUTF8Unsafe(), db);
+  return leveldb_env::DBRegistry::Open(options, file_path_.AsUTF8Unsafe(), db);
 }
 
 bool SessionStorageDatabase::IsOpen() const {
   return db_.get() != NULL;
 }
 
 bool SessionStorageDatabase::CallerErrorCheck(bool ok) const {
   DCHECK(ok);
   return ok;
 }
@@ skipping 329 matching lines @@
 std::string SessionStorageDatabase::MapKey(const std::string& map_id,
                                            const std::string& key) {
   return base::StringPrintf("map-%s-%s", map_id.c_str(), key.c_str());
 }
 
 const char* SessionStorageDatabase::NextMapIdKey() {
   return "next-map-id";
 }
 
 }  // namespace content