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

chrome/browser/permissions/chooser_context_base.cc

Index: chrome/browser/permissions/chooser_context_base.cc
diff --git a/chrome/browser/permissions/chooser_context_base.cc b/chrome/browser/permissions/chooser_context_base.cc
index af7b37e5d9cfa23d26b65c776a4fd58ebdc96000..6ccdc07dc0275e243a02dd58b8ed3058315d7336 100644
--- a/chrome/browser/permissions/chooser_context_base.cc
+++ b/chrome/browser/permissions/chooser_context_base.cc
@@ -55,12 +55,8 @@ ChooserContextBase::GetGrantedObjects(const GURL& requesting_origin,
   if (!object_list)
     return results;
 
-  for (base::ListValue::iterator it = object_list->begin();
-       it != object_list->end(); ++it) {
+  for (auto& object : *object_list) {
     // Steal ownership of |object| from |object_list|.
-    std::unique_ptr<base::Value> object(*it);
-    *it = nullptr;
-
     std::unique_ptr<base::DictionaryValue> object_dict =
         base::DictionaryValue::From(std::move(object));
     if (object_dict && IsValidObject(*object_dict))
@@ -88,7 +84,7 @@ ChooserContextBase::GetAllGrantedObjects() {
     if (!setting->GetList(kObjectListKey, &object_list))
       continue;
 
-    for (base::Value* object : *object_list) {
+    for (const auto& object : *object_list) {
       base::DictionaryValue* object_dict;
       if (!object->GetAsDictionary(&object_dict) ||
           !IsValidObject(*object_dict)) {