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

components/drive/resource_metadata_storage.cc

Index: components/drive/resource_metadata_storage.cc
diff --git a/components/drive/resource_metadata_storage.cc b/components/drive/resource_metadata_storage.cc
index 0c49407ccf1fb4cd129ea8f343c62c513d9f761c..f32000000d38226cde41a9d03dfc5f0dbc7c4000 100644
--- a/components/drive/resource_metadata_storage.cc
+++ b/components/drive/resource_metadata_storage.cc
@@ -274,7 +274,7 @@ bool ResourceMetadataStorage::UpgradeOldDB(
   options.max_open_files = 0;  // Use minimum.
   options.create_if_missing = false;
   options.reuse_logs = leveldb_env::kDefaultLogReuseOptionValue;
-  if (!leveldb::DB::Open(options, resource_map_path.AsUTF8Unsafe(), &db).ok())
+  if (!leveldb_env::DBRegistry::Open(options, resource_map_path.AsUTF8Unsafe(), &db).ok())
     return false;
   std::unique_ptr<leveldb::DB> resource_map(db);
 
@@ -561,7 +561,7 @@ bool ResourceMetadataStorage::Initialize() {
   DBInitStatus open_existing_result = DB_INIT_NOT_FOUND;
   leveldb::Status status;
   if (base::PathExists(resource_map_path)) {
-    status = leveldb::DB::Open(options, resource_map_path.AsUTF8Unsafe(), &db);
+    status = leveldb_env::DBRegistry::Open(options, resource_map_path.AsUTF8Unsafe(), &db);
     open_existing_result = LevelDBStatusToDBInitStatus(status);
   }
 
@@ -610,7 +610,7 @@ bool ResourceMetadataStorage::Initialize() {
     options.error_if_exists = true;
     options.reuse_logs = leveldb_env::kDefaultLogReuseOptionValue;
 
-    status = leveldb::DB::Open(options, resource_map_path.AsUTF8Unsafe(), &db);
+    status = leveldb_env::DBRegistry::Open(options, resource_map_path.AsUTF8Unsafe(), &db);
     if (status.ok()) {
       resource_map_.reset(db);
 
@@ -677,7 +677,7 @@ void ResourceMetadataStorage::RecoverCacheInfoFromTrashedResourceMap(
 
   // Open it.
   leveldb::DB* db = NULL;
-  status = leveldb::DB::Open(options, trashed_resource_map_path.AsUTF8Unsafe(),
+  status = leveldb_env::DBRegistry::Open(options, trashed_resource_map_path.AsUTF8Unsafe(),
                              &db);
   if (!status.ok()) {
     LOG(ERROR) << "Failed to open trashed DB: " << status.ToString();