Remove PersistentPrefStore::MarkNeedsEmptyValue.

base/prefs/json_pref_store.cc

Index: base/prefs/json_pref_store.cc
diff --git a/base/prefs/json_pref_store.cc b/base/prefs/json_pref_store.cc
index 04479753c3aad7b98e41370d09133d746e415d83..169e300595e9c3937add3e865f6e2f15b33208e7 100644
--- a/base/prefs/json_pref_store.cc
+++ b/base/prefs/json_pref_store.cc
@@ -218,14 +218,10 @@ void JsonPrefStore::SetValueSilently(const std::string& key, Value* value) {
 }
 
 void JsonPrefStore::RemoveValue(const std::string& key) {
-  if (prefs_->Remove(key, NULL))
+  if (prefs_->RemovePath(key, NULL))
     ReportValueChanged(key);
 }
 
-void JsonPrefStore::MarkNeedsEmptyValue(const std::string& key) {
-  keys_need_empty_value_.insert(key);
-}
-
 bool JsonPrefStore::ReadOnly() const {
   return read_only_;
 }
@@ -328,30 +324,5 @@ bool JsonPrefStore::SerializeData(std::string* output) {
   // value?
   JSONStringValueSerializer serializer(output);
   serializer.set_pretty_print(true);
-  scoped_ptr<DictionaryValue> copy(prefs_->DeepCopyWithoutEmptyChildren());
-
-  // Iterates |keys_need_empty_value_| and if the key exists in |prefs_|,
-  // ensure its empty ListValue or DictonaryValue is preserved.
-  for (std::set<std::string>::const_iterator
-       it = keys_need_empty_value_.begin();
-       it != keys_need_empty_value_.end();
-       ++it) {
-    const std::string& key = *it;
-
-    base::Value* value = NULL;
-    if (!prefs_->Get(key, &value))
-      continue;
-
-    if (value->IsType(base::Value::TYPE_LIST)) {
-      const base::ListValue* list = NULL;
-      if (value->GetAsList(&list) && list->empty())
-        copy->Set(key, new base::ListValue);
-    } else if (value->IsType(base::Value::TYPE_DICTIONARY)) {
-      const base::DictionaryValue* dict = NULL;
-      if (value->GetAsDictionary(&dict) && dict->empty())
-        copy->Set(key, new base::DictionaryValue);
-    }
-  }
-
-  return serializer.Serialize(*(copy.get()));
+  return serializer.Serialize(*prefs_);
 }