Upgrade Symbol implementation to match current ES6 behavior.

src/objects.cc

 // Copyright 2013 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 62 matching lines @@
 }
 
 
 MaybeObject* Object::ToObject(Context* native_context) {
   if (IsNumber()) {
     return CreateJSValue(native_context->number_function(), this);
   } else if (IsBoolean()) {
     return CreateJSValue(native_context->boolean_function(), this);
   } else if (IsString()) {
     return CreateJSValue(native_context->string_function(), this);
+  } else if (IsSymbol()) {
+    return CreateJSValue(native_context->symbol_function(), this);
   }
   ASSERT(IsJSObject());
   return this;
 }
 
 
 MaybeObject* Object::ToObject(Isolate* isolate) {
   if (IsJSReceiver()) {
     return this;
   } else if (IsNumber()) {
@@ skipping 16382 matching lines @@
 #define ERROR_MESSAGES_TEXTS(C, T) T,
   static const char* error_messages_[] = {
       ERROR_MESSAGES_LIST(ERROR_MESSAGES_TEXTS)
   };
 #undef ERROR_MESSAGES_TEXTS
   return error_messages_[reason];
 }
 
 
 } }  // namespace v8::internal