Remove Object::IsSpecObject, use Object::IsJSReceiver instead.

src/runtime/runtime-classes.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 <stdlib.h>
 #include <limits>
 
 #include "src/arguments.h"
@@ skipping 90 matching lines @@
             isolate,
             NewTypeError(MessageTemplate::kExtendsValueGenerator, super_class),
             Object);
       }
       ASSIGN_RETURN_ON_EXCEPTION(
           isolate, prototype_parent,
           Runtime::GetObjectProperty(isolate, super_class,
                                      isolate->factory()->prototype_string(),
                                      SLOPPY),
           Object);
-      if (!prototype_parent->IsNull() && !prototype_parent->IsSpecObject()) {
+      if (!prototype_parent->IsNull() && !prototype_parent->IsJSReceiver()) {
         THROW_NEW_ERROR(
             isolate, NewTypeError(MessageTemplate::kPrototypeParentNotAnObject,
                                   prototype_parent),
             Object);
       }
       constructor_parent = super_class;
     } else {
       THROW_NEW_ERROR(
           isolate,
           NewTypeError(MessageTemplate::kExtendsValueNotFunction, super_class),
@@ skipping 381 matching lines @@
   Handle<Object> result;
   ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
       isolate, result, Execution::New(isolate, super_constructor, new_target,
                                       argument_count, arguments.get()));
 
   return *result;
 }
 
 }  // namespace internal
 }  // namespace v8