Revert of "[es6] Partially implement Reflect.ownKeys."

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 3c675120fbcbd64bc3320398432298179f3329e4..c2421d019efcf51a71de4167346edb0f305fda2c 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -1833,7 +1833,6 @@ enum AccessorComponent {
 
 enum KeyFilter { SKIP_SYMBOLS, INCLUDE_SYMBOLS };
 
-enum Enumerability { RESPECT_ENUMERABILITY, IGNORE_ENUMERABILITY };
 
 enum GetKeysConversion { KEEP_NUMBERS, CONVERT_TO_STRING };
 
@@ -1960,8 +1959,7 @@ class JSReceiver: public HeapObject {
   MUST_USE_RESULT static MaybeHandle<FixedArray> GetKeys(
       Handle<JSReceiver> object, KeyCollectionType type,
       KeyFilter filter = SKIP_SYMBOLS,
-      GetKeysConversion getConversion = KEEP_NUMBERS,
-      Enumerability enum_policy = RESPECT_ENUMERABILITY);
+      GetKeysConversion getConversion = KEEP_NUMBERS);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSReceiver);