[tools] Fix detect-builtins.js

tools/detect-builtins.js

 // Copyright 2014 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) {
 
   var GetProperties = function(this_name, object) {
     var result = {};
     try {
       var names = Object.getOwnPropertyNames(object);
     } catch(e) {
       return;
     }
     for (var i = 0; i < names.length; ++i) {
       var name = names[i];
       if (typeof object === "function") {
         if (name === "length" ||
             name === "name" ||
             name === "arguments" ||
             name === "caller" ||
             name === "prototype") {
           continue;
         }
       }
       // Avoid endless recursion.
       if (this_name === "prototype" && name === "constructor") continue;
+      // Avoid needless duplication.
+      if (this_name === "__PROTO__" && name === "constructor") continue;
       // Could get this from the parent, but having it locally is easier.
       var property = { "name": name };
       try {
         var value = object[name];
       } catch(e) {
         property.type = "getter";
         result[name] = property;
         continue;
       }
       var type = typeof value;
       property.type = type;
       if (type === "function") {
         property.length = value.length;
         property.prototype = GetProperties("prototype", value.prototype);
       }
-      property.properties = GetProperties(name, value);
+      if (type === "string" || type === "number") {
+        property.value = value;
+      } else {
+        property.properties = GetProperties(name, value);
+      }
       result[name] = property;
     }
+    // Print the __proto__ if it's not the default Object prototype.
+    if (typeof object === "object" && object.__proto__ !== null &&
+        !object.__proto__.hasOwnProperty("__proto__")) {
+      result.__PROTO__ = GetProperties("__PROTO__", object.__proto__);
+    }
     return result;
   };
 
   var g = GetProperties("", global, "");
   print(JSON.stringify(g, undefined, 2));
 
 })(this);  // Must wrap in anonymous closure or it'll detect itself as builtin.