Revert of Change base::Value::ListStorage to std::vector<base::Value>

components/signin/core/browser/account_tracker_service.cc

Index: components/signin/core/browser/account_tracker_service.cc
diff --git a/components/signin/core/browser/account_tracker_service.cc b/components/signin/core/browser/account_tracker_service.cc
index 129b124288cce69c893e1cf8f34592ede9156bc3..dd3f339588f5271a1768459b8c98207ef76930f0 100644
--- a/components/signin/core/browser/account_tracker_service.cc
+++ b/components/signin/core/browser/account_tracker_service.cc
@@ -350,7 +350,7 @@
           contains_deprecated_service_flags = true;
           std::string flag_string;
           for (const auto& flag : *service_flags_list) {
-            if (flag.GetAsString(&flag_string) &&
+            if (flag->GetAsString(&flag_string) &&
                 flag_string == kChildAccountServiceFlag) {
               is_child_account = true;
               break;
@@ -407,8 +407,6 @@
   if (!dict) {
     dict = new base::DictionaryValue();
     update->Append(base::WrapUnique(dict));
-    // |dict| is invalidated at this point, so it needs to be reset.
-    update->GetDictionary(update->GetSize() - 1, &dict);
     dict->SetString(kAccountKeyPath, account_id_16);
   }