Use leveldb_env::OpenDB() to open leveldb databases.

extensions/browser/value_store/leveldb_value_store.cc

 // Copyright 2014 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 "extensions/browser/value_store/leveldb_value_store.h"
 
 #include <inttypes.h>
 #include <stdint.h>
 
 #include <utility>
@@ skipping 241 matching lines @@
   DCHECK(res);
   res = base::StringToUint64(value, &size);
   DCHECK(res);
 
   auto* dump = pmd->CreateAllocatorDump(base::StringPrintf(
       "leveldb/value_store/%s/0x%" PRIXPTR, open_histogram_name().c_str(),
       reinterpret_cast<uintptr_t>(this)));
   dump->AddScalar(base::trace_event::MemoryAllocatorDump::kNameSize,
                   base::trace_event::MemoryAllocatorDump::kUnitsBytes, size);
 
-  // Memory is allocated from system allocator (malloc).
-  const char* system_allocator_name =
-      base::trace_event::MemoryDumpManager::GetInstance()
-          ->system_allocator_pool_name();
-  if (system_allocator_name)
-    pmd->AddSuballocation(dump->guid(), system_allocator_name);
+  // All leveldb databases are already dumped by leveldb_env::DBTracker. Add
+  // an edge to avoid double counting.
+  pmd->AddSuballocation(dump->guid(),
+                        leveldb_env::DBTracker::GetMemoryDumpName(db()));
 
   return true;
 }
 
 ValueStore::Status LeveldbValueStore::AddToBatch(
     ValueStore::WriteOptions options,
     const std::string& key,
     const base::Value& value,
     leveldb::WriteBatch* batch,
     ValueStoreChangeList* changes) {
@@ skipping 18 matching lines @@
       return Status(OTHER_ERROR, kCannotSerialize);
     batch->Put(key, value_as_json);
   }
 
   return Status();
 }
 
 ValueStore::Status LeveldbValueStore::WriteToDb(leveldb::WriteBatch* batch) {
   return ToValueStoreError(db()->Write(write_options(), batch));
 }