Use std::unique_ptr for base::DictionaryValue and base::ListValue's internal store.

chrome/browser/chromeos/login/ui/webui_login_view.cc

Index: chrome/browser/chromeos/login/ui/webui_login_view.cc
diff --git a/chrome/browser/chromeos/login/ui/webui_login_view.cc b/chrome/browser/chromeos/login/ui/webui_login_view.cc
index 2bc53aa8e0d80744cf12ad315954155a8fdd35ec..d4b7772230c3b311794e60c6fa760cf6a4ff587d 100644
--- a/chrome/browser/chromeos/login/ui/webui_login_view.cc
+++ b/chrome/browser/chromeos/login/ui/webui_login_view.cc
@@ -478,7 +478,7 @@ void WebUILoginView::RequestMediaAccessPermission(
 
   const base::ListValue* list_value;
   CHECK(raw_list_value->GetAsList(&list_value));
-  for (base::Value* base_value : *list_value) {
+  for (const auto& base_value : *list_value) {
     std::string value;
     if (base_value->GetAsString(&value)) {
       ContentSettingsPattern pattern =