Addressed perf regression in Browsermark2.0 array blur test

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 843 matching lines @@
   inline void set_##name(bool value);  \
 
 
 #define DECL_ACCESSORS(name, type)                                      \
   inline type* name();                                                  \
   inline void set_##name(type* value,                                   \
                          WriteBarrierMode mode = UPDATE_WRITE_BARRIER); \
 
 class AccessorPair;
 class AllocationSite;
-class AllocationSiteContext;
+class AllocationSiteCreationContext;
+class AllocationSiteUsageContext;
 class DictionaryElementsAccessor;
 class ElementsAccessor;
 class Failure;
 class FixedArrayBase;
 class ObjectVisitor;
 class StringStream;
 class Type;
 
 
 // A template-ized version of the IsXXX functions.
@@ skipping 1639 matching lines @@
   // Disalow further properties to be added to the object.
   static Handle<Object> PreventExtensions(Handle<JSObject> object);
 
   // ES5 Object.freeze
   static Handle<Object> Freeze(Handle<JSObject> object);
 
   // Called the first time an object is observed with ES7 Object.observe.
   static void SetObserved(Handle<JSObject> object);
 
   // Copy object.
-  static Handle<JSObject> Copy(Handle<JSObject> object,
-                               Handle<AllocationSite> site);
+  enum DeepCopyHints {
+    kNoHints = 0,
+    kObjectIsShallowArray = 1
+  };
+
   static Handle<JSObject> Copy(Handle<JSObject> object);
   static Handle<JSObject> DeepCopy(Handle<JSObject> object,
-                                   AllocationSiteContext* site_context);
+                                   AllocationSiteUsageContext* site_context,
+                                   DeepCopyHints hints = kNoHints);
   static Handle<JSObject> DeepWalk(Handle<JSObject> object,
-                                   AllocationSiteContext* site_context);
+                                   AllocationSiteCreationContext* site_context);
 
   // Casting.
   static inline JSObject* cast(Object* obj);
 
   // Dispatched behavior.
   void JSObjectShortPrint(StringStream* accumulator);
   DECLARE_PRINTER(JSObject)
   DECLARE_VERIFIER(JSObject)
 #ifdef OBJECT_PRINT
   void PrintProperties(FILE* out = stdout);
@@ skipping 8025 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_