Revert of [builtins] Also port the Object.prototype.__proto__ accessors to C++.

src/runtime/runtime-object.cc

Index: src/runtime/runtime-object.cc
diff --git a/src/runtime/runtime-object.cc b/src/runtime/runtime-object.cc
index 67978c8604a9c2d6b727653fa46d9f2670a0b53c..6cb6083a9ff68bc864b4d3d639b0554ca82b5291 100644
--- a/src/runtime/runtime-object.cc
+++ b/src/runtime/runtime-object.cc
@@ -250,6 +250,18 @@
   return *obj;
 }
 
+
+RUNTIME_FUNCTION(Runtime_SetPrototype) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(JSReceiver, obj, 0);
+  CONVERT_ARG_HANDLE_CHECKED(Object, prototype, 1);
+  MAYBE_RETURN(
+      JSReceiver::SetPrototype(obj, prototype, true, Object::THROW_ON_ERROR),
+      isolate->heap()->exception());
+  return *obj;
+}
+
 RUNTIME_FUNCTION(Runtime_OptimizeObjectForAddingMultipleProperties) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);