Made PropertyType handling even more explicit.

src/property.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 244 matching lines @@
   bool IsReadOnly() { return details_.IsReadOnly(); }
   bool IsDontDelete() { return details_.IsDontDelete(); }
   bool IsDontEnum() { return details_.IsDontEnum(); }
   bool IsDeleted() { return details_.IsDeleted(); }
   bool IsFound() { return lookup_type_ != NOT_FOUND; }
   bool IsHandler() { return lookup_type_ == HANDLER_TYPE; }
 
   // Is the result is a property excluding transitions and the null
   // descriptor?
   bool IsProperty() {
-    return IsFound() && (type() < FIRST_PHANTOM_PROPERTY_TYPE);
+    return IsFound() && GetPropertyDetails().IsProperty();
   }
 
   // Is the result a property or a transition?
   bool IsPropertyOrTransition() {
     return IsFound() && (type() != NULL_DESCRIPTOR);
   }
 
   bool IsCacheable() { return cacheable_; }
   void DisallowCaching() { cacheable_ = false; }
 
@@ skipping 100 matching lines @@
   JSReceiver* holder_;
   int number_;
   bool cacheable_;
   PropertyDetails details_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_PROPERTY_H_