[runtime] Remove the redundant %_IsObject intrinsic.

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/messages.h"
@@ skipping 1345 matching lines @@
 
 RUNTIME_FUNCTION(Runtime_ObjectEquals) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_CHECKED(Object, obj1, 0);
   CONVERT_ARG_CHECKED(Object, obj2, 1);
   return isolate->heap()->ToBoolean(obj1 == obj2);
 }
 
 
-RUNTIME_FUNCTION(Runtime_IsObject) {
-  SealHandleScope shs(isolate);
-  DCHECK(args.length() == 1);
-  CONVERT_ARG_CHECKED(Object, obj, 0);
-  if (!obj->IsHeapObject()) return isolate->heap()->false_value();
-  if (obj->IsNull()) return isolate->heap()->true_value();
-  if (obj->IsUndetectableObject()) return isolate->heap()->false_value();
-  Map* map = HeapObject::cast(obj)->map();
-  bool is_non_callable_spec_object =
-      map->instance_type() >= FIRST_NONCALLABLE_SPEC_OBJECT_TYPE &&
-      map->instance_type() <= LAST_NONCALLABLE_SPEC_OBJECT_TYPE;
-  return isolate->heap()->ToBoolean(is_non_callable_spec_object);
-}
-
-
 RUNTIME_FUNCTION(Runtime_IsSpecObject) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 1);
   CONVERT_ARG_CHECKED(Object, obj, 0);
   return isolate->heap()->ToBoolean(obj->IsSpecObject());
 }
 
 
 RUNTIME_FUNCTION(Runtime_IsStrong) {
   SealHandleScope shs(isolate);
@@ skipping 116 matching lines @@
   SealHandleScope scope(isolate);
   DCHECK_EQ(2, args.length());
   CONVERT_ARG_CHECKED(Object, object, 0);
   CONVERT_ARG_CHECKED(Object, prototype, 1);
   return isolate->heap()->ToBoolean(
       object->HasInPrototypeChain(isolate, prototype));
 }
 
 }  // namespace internal
 }  // namespace v8