Add API for access checks on observed objects

src/objects.h

 // Copyright 2012 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 8331 matching lines @@
   }
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(AccessorPair);
 };
 
 
 class AccessCheckInfo: public Struct {
  public:
   DECL_ACCESSORS(named_callback, Object)
   DECL_ACCESSORS(indexed_callback, Object)
+  DECL_ACCESSORS(observe_callback, Object)
   DECL_ACCESSORS(data, Object)
 
   static inline AccessCheckInfo* cast(Object* obj);
 
   // Dispatched behavior.
   DECLARE_PRINTER(AccessCheckInfo)
   DECLARE_VERIFIER(AccessCheckInfo)
 
   static const int kNamedCallbackOffset   = HeapObject::kHeaderSize;
   static const int kIndexedCallbackOffset = kNamedCallbackOffset + kPointerSize;
-  static const int kDataOffset = kIndexedCallbackOffset + kPointerSize;
+  static const int kObserveCallbackOffset =
+      kIndexedCallbackOffset + kPointerSize;
+  static const int kDataOffset = kObserveCallbackOffset + kPointerSize;
   static const int kSize = kDataOffset + kPointerSize;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(AccessCheckInfo);
 };
 
 
 class InterceptorInfo: public Struct {
  public:
   DECL_ACCESSORS(getter, Object)
@@ skipping 413 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_