Replace CopyMap(constructor->initial_map()) by Map::Create(constructor)

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 6206 matching lines @@
   // deprecated, it is directly returned. Otherwise, the non-deprecated version
   // is found by re-transitioning from the root of the transition tree using the
   // descriptor array of the map. Returns NULL if no updated map is found.
   // This method also applies any pending migrations along the prototype chain.
   static Handle<Map> CurrentMapForDeprecated(Handle<Map> map);
   // Same as above, but does not touch the prototype chain.
   static Handle<Map> CurrentMapForDeprecatedInternal(Handle<Map> map);
 
   static Handle<Map> RawCopy(Handle<Map> map, int instance_size);
   MUST_USE_RESULT MaybeObject* RawCopy(int instance_size);
-  MUST_USE_RESULT MaybeObject* CopyWithPreallocatedFieldDescriptors();
   static Handle<Map> CopyDropDescriptors(Handle<Map> map);
   MUST_USE_RESULT MaybeObject* CopyDropDescriptors();
   static Handle<Map> CopyReplaceDescriptors(Handle<Map> map,
                                             Handle<DescriptorArray> descriptors,
                                             TransitionFlag flag,
                                             Handle<Name> name);
   MUST_USE_RESULT MaybeObject* CopyReplaceDescriptors(
       DescriptorArray* descriptors,
       TransitionFlag flag,
       Name* name = NULL,
@@ skipping 26 matching lines @@
   static Handle<Map> CopyNormalized(Handle<Map> map,
                                     PropertyNormalizationMode mode,
                                     NormalizedMapSharingMode sharing);
 
   inline void AppendDescriptor(Descriptor* desc,
                                const DescriptorArray::WhitenessWitness&);
 
   // Returns a copy of the map, with all transitions dropped from the
   // instance descriptors.
   static Handle<Map> Copy(Handle<Map> map);
+  static Handle<Map> Create(Handle<JSFunction> constructor,
+                            int extra_inobject_properties);
   MUST_USE_RESULT MaybeObject* Copy();
 
   // Returns the next free property index (only valid for FAST MODE).
   int NextFreePropertyIndex();
 
   // Returns the number of properties described in instance_descriptors
   // filtering out properties with the specified attributes.
   int NumberOfDescribedProperties(DescriptorFlag which = OWN_DESCRIPTORS,
                                   PropertyAttributes filter = NONE);
 
@@ skipping 4544 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_