[runtime] Use utils.InstallFunctions for Symbol.prototype[@@toPrimitive].

src/symbol.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 (function(global, utils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
@@ skipping 101 matching lines @@
   "unscopables", unscopablesSymbol,
 ]);
 
 utils.InstallFunctions(GlobalSymbol, DONT_ENUM, [
   "for", SymbolFor,
   "keyFor", SymbolKeyFor
 ]);
 
 %AddNamedProperty(
     GlobalSymbol.prototype, "constructor", GlobalSymbol, DONT_ENUM);
-utils.SetFunctionName(SymbolToPrimitive, toPrimitiveSymbol);
-%AddNamedProperty(
-    GlobalSymbol.prototype, toPrimitiveSymbol, SymbolToPrimitive,
-    DONT_ENUM | READ_ONLY);
 %AddNamedProperty(
     GlobalSymbol.prototype, toStringTagSymbol, "Symbol", DONT_ENUM | READ_ONLY);
 
+utils.InstallFunctions(GlobalSymbol.prototype, DONT_ENUM | READ_ONLY, [
+  toPrimitiveSymbol, SymbolToPrimitive
+]);
+
 utils.InstallFunctions(GlobalSymbol.prototype, DONT_ENUM, [
   "toString", SymbolToString,
   "valueOf", SymbolValueOf
 ]);
 
 utils.InstallFunctions(GlobalObject, DONT_ENUM, [
   "getOwnPropertySymbols", ObjectGetOwnPropertySymbols
 ]);
 
 // -------------------------------------------------------------------
 // Exports
 
 utils.Export(function(to) {
   to.SymbolToString = SymbolToString;
 })
 
 })