Added ability to remove prototype from function. In this case, [[Construct]] ...

src/objects.h

 // Copyright 2006-2009 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 2836 matching lines @@
   inline void set_bit_field2(byte value);
 
   // Tells whether the object in the prototype property will be used
   // for instances created from this function.  If the prototype
   // property is set to a value that is not a JSObject, the prototype
   // property will not be used to create instances of the function.
   // See ECMA-262, 13.2.2.
   inline void set_non_instance_prototype(bool value);
   inline bool has_non_instance_prototype();
 
+  // Tells whether function has special prototype property. If not, prototype
+  // property will not be created when accessed (will return undefined),
+  // and construction from this function will not be allowed.
+  inline void set_function_with_prototype(bool value);
+  inline bool function_with_prototype();
+
   // Tells whether the instance with this map should be ignored by the
   // __proto__ accessor.
   inline void set_is_hidden_prototype() {
     set_bit_field(bit_field() | (1 << kIsHiddenPrototype));
   }
 
   inline bool is_hidden_prototype() {
     return ((1 << kIsHiddenPrototype) & bit_field()) != 0;
   }
 
@@ skipping 156 matching lines @@
   static const int kHasNonInstancePrototype = 1;
   static const int kIsHiddenPrototype = 2;
   static const int kHasNamedInterceptor = 3;
   static const int kHasIndexedInterceptor = 4;
   static const int kIsUndetectable = 5;
   static const int kHasInstanceCallHandler = 6;
   static const int kIsAccessCheckNeeded = 7;
 
   // Bit positions for bit field 2
   static const int kIsExtensible = 0;
+  static const int kFunctionWithPrototype = 1;
 
   // Layout of the default cache. It holds alternating name and code objects.
   static const int kCodeCacheEntrySize = 2;
   static const int kCodeCacheEntryNameOffset = 0;
   static const int kCodeCacheEntryCodeOffset = 1;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(Map);
 };
 
@@ skipping 346 matching lines @@
   // function has an initial map the prototype is set on the initial
   // map. Otherwise, the prototype is put in the initial map field
   // until an initial map is needed.
   inline bool has_prototype();
   inline bool has_instance_prototype();
   inline Object* prototype();
   inline Object* instance_prototype();
   Object* SetInstancePrototype(Object* value);
   Object* SetPrototype(Object* value);
 
+  // After prototype is removed, it will not be created when accessed, and
+  // [[Construct]] from this function will not be allowed.
+  Object* RemovePrototype();
+  inline bool should_have_prototype();
+
   // Accessor for this function's initial map's [[class]]
   // property. This is primarily used by ECMA native functions.  This
   // method sets the class_name field of this function's initial map
   // to a given value. It creates an initial map if this function does
   // not have one. Note that this method does not copy the initial map
   // if it has one already, but simply replaces it with the new value.
   // Instances created afterwards will have a map whose [[class]] is
   // set to 'value', but there is no guarantees on instances created
   // before.
   Object* SetInstanceClassName(String* name);
@@ skipping 1724 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_