[Privet Filesystem] Fix null dereference

chrome/browser/local_discovery/storage/privet_filesystem_operations.cc

Index: chrome/browser/local_discovery/storage/privet_filesystem_operations.cc
diff --git a/chrome/browser/local_discovery/storage/privet_filesystem_operations.cc b/chrome/browser/local_discovery/storage/privet_filesystem_operations.cc
index 99e9c2febcd2557cdb7494e1c2af96f5e9b353b4..a7095ae3193b788ab7eea15b823cb79007999425 100644
--- a/chrome/browser/local_discovery/storage/privet_filesystem_operations.cc
+++ b/chrome/browser/local_discovery/storage/privet_filesystem_operations.cc
@@ -149,15 +149,15 @@ void PrivetFileSystemListOperation::OnStorageListResult(
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   list_operation_.reset();
 
-  attribute_cache_->AddFileInfoFromJSON(full_path_, value);
-
-  fileapi::AsyncFileUtil::EntryList entry_list;
-
   if (!value) {
     SignalError();
     return;
   }
 
+  attribute_cache_->AddFileInfoFromJSON(full_path_, value);
+
+  fileapi::AsyncFileUtil::EntryList entry_list;
+
   const base::ListValue* entries;
   if (!value->GetList(kPrivetListEntries, &entries)) {
     SignalError();