[runtime] Do not use the enum-cache for non-prototype objects.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 429bd49c3399ec2d8bb620d1d46501ad840a1cf2..1d6ac68d06556f5deeb3e41ce00692ab463993b7 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -2284,9 +2284,6 @@ class JSObject: public JSReceiver {
   inline void SetInternalField(int index, Object* value);
   inline void SetInternalField(int index, Smi* value);
 
-  void CollectOwnPropertyNames(KeyAccumulator* keys,
-                               PropertyFilter filter = ALL_PROPERTIES);
-
   // Returns the number of properties on this object filtering out properties
   // with the specified attributes (ignoring interceptors).
   // TODO(jkummerow): Deprecated, only used by Object.observe.
@@ -2296,10 +2293,13 @@ class JSObject: public JSReceiver {
   // TODO(jkummerow): Deprecated, only used by Object.observe.
   int GetOwnElementKeys(FixedArray* storage, PropertyFilter filter);
 
+  void CollectOwnPropertyKeys(
+      KeyAccumulator* keys, PropertyFilter filter = ALL_PROPERTIES,
+      JSReceiver::KeyCollectionType type = JSReceiver::OWN_ONLY);
+
   static void CollectOwnElementKeys(Handle<JSObject> object,
                                     KeyAccumulator* keys,
                                     PropertyFilter filter);
-
   static Handle<FixedArray> GetEnumPropertyKeys(Handle<JSObject> object,
                                                 bool cache_result);