Revert r8619 because of Webkit failures.

src/handles.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 409 matching lines @@
   CALL_HEAP_FUNCTION(object->GetIsolate(), object->PreventExtensions(), Object);
 }
 
 
 Handle<Object> GetHiddenProperties(Handle<JSObject> obj,
                                    bool create_if_needed) {
   Isolate* isolate = obj->GetIsolate();
   Object* holder = obj->BypassGlobalProxy();
   if (holder->IsUndefined()) return isolate->factory()->undefined_value();
   obj = Handle<JSObject>(JSObject::cast(holder), isolate);
-  CALL_HEAP_FUNCTION(isolate,
-                     obj->GetHiddenProperties(create_if_needed),
-                     Object);
+
+  if (obj->HasFastProperties()) {
+    // If the object has fast properties, check whether the first slot
+    // in the descriptor array matches the hidden symbol. Since the
+    // hidden symbols hash code is zero (and no other string has hash
+    // code zero) it will always occupy the first entry if present.
+    DescriptorArray* descriptors = obj->map()->instance_descriptors();
+    if ((descriptors->number_of_descriptors() > 0) &&
+        (descriptors->GetKey(0) == isolate->heap()->hidden_symbol()) &&
+        descriptors->IsProperty(0)) {
+      ASSERT(descriptors->GetType(0) == FIELD);
+      return Handle<Object>(obj->FastPropertyAt(descriptors->GetFieldIndex(0)),
+                            isolate);
+    }
+  }
+
+  // Only attempt to find the hidden properties in the local object and not
+  // in the prototype chain.  Note that HasLocalProperty() can cause a GC in
+  // the general case in the presence of interceptors.
+  if (!obj->HasHiddenPropertiesObject()) {
+    // Hidden properties object not found. Allocate a new hidden properties
+    // object if requested. Otherwise return the undefined value.
+    if (create_if_needed) {
+      Handle<Object> hidden_obj =
+          isolate->factory()->NewJSObject(isolate->object_function());
+      CALL_HEAP_FUNCTION(isolate,
+                         obj->SetHiddenPropertiesObject(*hidden_obj), Object);
+    } else {
+      return isolate->factory()->undefined_value();
+    }
+  }
+  return Handle<Object>(obj->GetHiddenPropertiesObject(), isolate);
 }
 
 
-Handle<Smi> GetIdentityHash(Handle<JSObject> obj) {
-  CALL_HEAP_FUNCTION(obj->GetIsolate(), obj->GetIdentityHash(), Smi);
-}
-
-
 Handle<Object> DeleteElement(Handle<JSObject> obj,
                              uint32_t index) {
   CALL_HEAP_FUNCTION(obj->GetIsolate(),
                      obj->DeleteElement(index, JSObject::NORMAL_DELETION),
                      Object);
 }
 
 
 Handle<Object> DeleteProperty(Handle<JSObject> obj,
                               Handle<String> prop) {
@@ skipping 491 matching lines @@
 
 bool CompileOptimized(Handle<JSFunction> function,
                       int osr_ast_id,
                       ClearExceptionFlag flag) {
   CompilationInfo info(function);
   info.SetOptimizing(osr_ast_id);
   return CompileLazyHelper(&info, flag);
 }
 
 } }  // namespace v8::internal