ES6 symbols: prevent reflection and proxy APIs from leaking symbols

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 9d39157ec2c329f236e43a3bb84a2e01e561e696..fc673c282928f2bd3699b9c8f72c54e664c78f80 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -2057,7 +2057,8 @@ class JSObject: public JSReceiver {
   int NumberOfLocalProperties(PropertyAttributes filter = NONE);
   // Fill in details for properties into storage starting at the specified
   // index.
-  void GetLocalPropertyNames(FixedArray* storage, int index);
+  void GetLocalPropertyNames(
+      FixedArray* storage, int index, PropertyAttributes filter = NONE);
 
   // Returns the number of properties on this object filtering out properties
   // with the specified attributes (ignoring interceptors).
@@ -3255,7 +3256,10 @@ class Dictionary: public HashTable<Shape, Key> {
                   PropertyAttributes filter,
                   SortMode sort_mode);
   // Fill in details for properties into storage.
-  void CopyKeysTo(FixedArray* storage, int index, SortMode sort_mode);
+  void CopyKeysTo(FixedArray* storage,
+                  int index,
+                  PropertyAttributes filter,
+                  SortMode sort_mode);
 
   // Accessors for next enumeration index.
   void SetNextEnumerationIndex(int index) {