ES6 symbols: implement name property

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 7380 matching lines @@
   static inline bool IsHashFieldComputed(uint32_t field);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(Name);
 };
 
 
 // ES6 symbols.
 class Symbol: public Name {
  public:
+  // [name]: the print name of a symbol, or undefined if none.
+  DECL_ACCESSORS(name, Object)
+
   // Casting.
   static inline Symbol* cast(Object* obj);
 
   // Dispatched behavior.
   DECLARE_PRINTER(Symbol)
   DECLARE_VERIFIER(Symbol)
 
   // Layout description.
-  static const int kSize = Name::kSize;
+  static const int kNameOffset = Name::kSize;
+  static const int kSize = kNameOffset + kPointerSize;
+
+  typedef FixedBodyDescriptor<kNameOffset, kNameOffset + kPointerSize, kSize>
+          BodyDescriptor;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(Symbol);
 };
 
 
 class ConsString;
 
 // The String abstract class captures JavaScript string values:
 //
@@ skipping 1838 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_