Move some code from Runtime_GetPrototype into a new Object::GetPrototype.

src/runtime/runtime-object.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/bootstrapper.h"
 #include "src/debug/debug.h"
 #include "src/isolate-inl.h"
@@ skipping 139 matching lines @@
 
   return Object::SetProperty(&it, value, language_mode,
                              Object::MAY_BE_STORE_FROM_KEYED);
 }
 
 
 RUNTIME_FUNCTION(Runtime_GetPrototype) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, obj, 0);
-  // We don't expect access checks to be needed on JSProxy objects.
-  DCHECK(!obj->IsAccessCheckNeeded() || obj->IsJSObject());
-  PrototypeIterator iter(isolate, obj, PrototypeIterator::START_AT_RECEIVER);
-  Handle<Context> context(isolate->context());
-  do {
-    if (PrototypeIterator::GetCurrent(iter)->IsAccessCheckNeeded() &&
-        !isolate->MayAccess(context,
-                            PrototypeIterator::GetCurrent<JSObject>(iter))) {
-      return isolate->heap()->null_value();
-    }
-    iter.AdvanceIgnoringProxies();
-    if (PrototypeIterator::GetCurrent(iter)->IsJSProxy()) {
-      return *PrototypeIterator::GetCurrent(iter);
-    }
-  } while (!iter.IsAtEnd(PrototypeIterator::END_AT_NON_HIDDEN));
-  return *PrototypeIterator::GetCurrent(iter);
+  return *Object::GetPrototype(isolate, obj);
 }
 
 
 RUNTIME_FUNCTION(Runtime_InternalSetPrototype) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, obj, 0);
   CONVERT_ARG_HANDLE_CHECKED(Object, prototype, 1);
   DCHECK(!obj->IsAccessCheckNeeded());
   DCHECK(!obj->map()->is_observed());
   Handle<Object> result;
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
       isolate, result, JSObject::SetPrototype(obj, prototype, false));
   return *result;
 }
 
 
 RUNTIME_FUNCTION(Runtime_SetPrototype) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, obj, 0);
   CONVERT_ARG_HANDLE_CHECKED(Object, prototype, 1);
   if (obj->IsAccessCheckNeeded() &&
       !isolate->MayAccess(handle(isolate->context()), obj)) {
     isolate->ReportFailedAccessCheck(obj);
     RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate);
     return isolate->heap()->undefined_value();
   }
   if (obj->map()->is_observed()) {
-    Handle<Object> old_value =
-        Object::GetPrototypeSkipHiddenPrototypes(isolate, obj);
+    Handle<Object> old_value = Object::GetPrototypeWithAccess(isolate, obj);
     Handle<Object> result;
     ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
         isolate, result, JSObject::SetPrototype(obj, prototype, true));
 
-    Handle<Object> new_value =
-        Object::GetPrototypeSkipHiddenPrototypes(isolate, obj);
+    Handle<Object> new_value = Object::GetPrototypeWithAccess(isolate, obj);
     if (!new_value->SameValue(*old_value)) {
       RETURN_FAILURE_ON_EXCEPTION(
           isolate, JSObject::EnqueueChangeRecord(
                        obj, "setPrototype", isolate->factory()->proto_string(),
                        old_value));
     }
     return *result;
   }
   Handle<Object> result;
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
@@ skipping 1399 matching lines @@
 RUNTIME_FUNCTION(Runtime_IsAccessCheckNeeded) {
   SealHandleScope shs(isolate);
   DCHECK_EQ(1, args.length());
   CONVERT_ARG_CHECKED(Object, object, 0);
   return isolate->heap()->ToBoolean(object->IsAccessCheckNeeded());
 }
 
 
 }  // namespace internal
 }  // namespace v8