Remove PersistentPrefStore::MarkNeedsEmptyValue.

base/values.cc

Index: base/values.cc
diff --git a/base/values.cc b/base/values.cc
index 9228ca9b7690cc4644a19a9fda6c8aa24fd56f40..5ec8d582998fe37bf26114890e308ef756f32962 100644
--- a/base/values.cc
+++ b/base/values.cc
@@ -462,8 +462,8 @@ void DictionaryValue::SetStringWithoutPathExpansion(
   SetWithoutPathExpansion(path, CreateStringValue(in_value));
 }
 
-bool DictionaryValue::Get(
-    const std::string& path, const Value** out_value) const {
+bool DictionaryValue::Get(const std::string& path,
+                          const Value** out_value) const {
   DCHECK(IsStringUTF8(path));
   std::string current_path(path);
   const DictionaryValue* current_dictionary = this;
@@ -751,6 +751,24 @@ bool DictionaryValue::RemoveWithoutPathExpansion(const std::string& key,
   return true;
 }
 
+bool DictionaryValue::RemovePath(const std::string& path, Value** out_value) {
+  bool result = false;
+  size_t delimiter_position = path.find('.');
+  if (delimiter_position == std::string::npos) {
+    return RemoveWithoutPathExpansion(path, out_value);
+  } else {
+    const std::string subdict_path = path.substr(0, delimiter_position);
+    DictionaryValue* subdict = NULL;
+    if (!GetDictionary(subdict_path, &subdict))
+      return false;
+    result = subdict->RemovePath(path.substr(delimiter_position + 1),
+                                 out_value);
+    if (result && subdict->empty())
+      Remove(subdict_path, NULL);
+  }
+  return result;
+}
+
 DictionaryValue* DictionaryValue::DeepCopyWithoutEmptyChildren() {
   Value* copy = CopyWithoutEmptyChildren(this);
   return copy ? static_cast<DictionaryValue*>(copy) : new DictionaryValue;