Introduce IsUndefined(Isolate*) and IsTheHole(Isolate*)

src/heap/heap-inl.h

 // Copyright 2012 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.
 
 #ifndef V8_HEAP_HEAP_INL_H_
 #define V8_HEAP_HEAP_INL_H_
 
 #include <cmath>
 
 #include "src/base/platform/platform.h"
@@ skipping 578 matching lines @@
 }
 
 
 // Verify() is inline to avoid ifdef-s around its calls in release
 // mode.
 void Heap::ExternalStringTable::Verify() {
 #ifdef DEBUG
   for (int i = 0; i < new_space_strings_.length(); ++i) {
     Object* obj = Object::cast(new_space_strings_[i]);
     DCHECK(heap_->InNewSpace(obj));
-    DCHECK(obj != heap_->the_hole_value());
+    DCHECK(!obj->IsTheHole(heap_->isolate()));
   }
   for (int i = 0; i < old_space_strings_.length(); ++i) {
     Object* obj = Object::cast(old_space_strings_[i]);
     DCHECK(!heap_->InNewSpace(obj));
-    DCHECK(obj != heap_->the_hole_value());
+    DCHECK(!obj->IsTheHole(heap_->isolate()));
   }
 #endif
 }
 
 
 void Heap::ExternalStringTable::AddOldString(String* string) {
   DCHECK(string->IsExternalString());
   DCHECK(!heap_->InNewSpace(string));
   old_space_strings_.Add(string);
 }
@@ skipping 119 matching lines @@
 
 void VerifySmisVisitor::VisitPointers(Object** start, Object** end) {
   for (Object** current = start; current < end; current++) {
     CHECK((*current)->IsSmi());
   }
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_HEAP_INL_H_